CHAPTER 25

Personality Disorders

Andrew E. Skodol, M.D.

Donna S. Bender, Ph.D.

John G. Gunderson, M.D.

John M. Oldham, M.D.

Personality disorders are associated with significant difficulties in self-appraisal and self-regulation, as well as with impaired interpersonal relationships. Clinicians frequently encounter patients with personality disorders in both outpatient and inpatient settings. Studies indicate that at least 50% of patients evaluated in clinical settings have a personality disorder (Zimmerman et al. 2005), often comorbid with another mental disorder, making personality disorders among the most frequent mental disorders seen by mental health professionals. Personality disorders are also common in the general population, with an estimated prevalence of about 10% (Torgersen 2009). Patients with personality disorders are among the most complex and clinically challenging.

General Considerations

What Is a Personality Disorder?

Personality disorders in DSM-5 Section II (American Psychiatric Association 2013) are defined by general criteria exactly as they were in DSM-IV-TR (American Psychiatric Association 2000), despite the absence of theoretical or empirical justification for key aspects of these criteria. According to DSM-5 Section II, personality disorders are enduring patterns of inner experience and behavior that are inflexible and pervasive and cause clinically significant distress or impairment in social, occupational, or other areas of functioning. The patterns deviate markedly from the expectations of an individual's culture and are said in DSM-5 Section II to manifest in two or more of the following areas: cognition, affectivity, interpersonal functioning, and impulse control. These features are not specific to personality disorders, however, and may characterize other chronic mental disorders, contributing to problems in differential diagnosis. An alternative set of general criteria was proposed for DSM-5 and is included in the Alternative DSM-5 Model for Personality Disorders in Section III of the manual. The alternative criteria focus on 1) impairments in aspects of personality functioning (Criterion A), including identity, self-direction, empathy, and intimacy, that have been shown to be core features of personality psychopathology (Bender et al. 2011) and have been empirically demonstrated to be specific for personality disorders (Morey et al. 2011), thereby facilitating differential diagnosis; and 2) pathological personality traits (Criterion B) which describe the myriad variations in personality pathology.

Other Characteristics of Personality Disorders

According to both the Section II and Section III definitions, the manifestations of personality pathology are relatively pervasive—that is, they are exhibited across a broad range of contexts and situations, rather than in only one specific triggering situation or in response to a particular stimulus or person. Although DSM-5 Section II states that the patterns must have been stably present and enduring since adolescence or early adulthood, the alternative criteria in Section III require that the core impairments in personality functioning and pathological personality traits must have been relatively stable across time and consistent across situations. This change from a concept of stability to relative stability is motivated by data from prospective, longitudinal, follow-along studies in both nonpatients (Lenzenweger et al. 2004) and patients (Gunderson et al. 2011; Zanarini et al. 2012) that consistently have found that the stability of disorder constructs is considerably less than that implied by DSM-IV-TR and that personality disorders have a clinical course that tends toward improvement or remission. In addition, both normal and pathological personality traits, while more stable than disorders, still change across the life span (Roberts and DelVecchio 2000). Thus, although shifting to a more trait-based set of criteria is expected to increase stability (Morey et al. 2007), allowance for some change is warranted.

A comparison of the Section II and Section III general criteria for personality disorder is presented in Table 25-1.

History of DSM Personality Disorders

Personality disorders have been included in every version of DSM, but only paranoid, obsessive-compulsive, and antisocial personality disorders have been consistent DSM "members" (Figure 25-1). Some current categories (e.g., borderline personality disorder) were added to later editions, whereas others (e.g., inadequate personality) were dropped. The theoretical underpinnings of the DSM personality disorder categories have also changed over the years.

DSM-I (American Psychiatric Association 1952) defined personality disorders not as stable and enduring patterns but as traits that malfunctioned under stressful circumstances, leading to inflexible and maladaptive behavior. DSM-II (American Psychiatric Association 1968) emphasized that personality disorders involved distress and impairment in functioning, not merely socially deviant behavior. In DSM III (American Psychiatric Association 1980), several major changes in personality disorder conceptualization and classification were made. There was a shift away from a psychoanalytic orientation and toward an atheoretical, descriptive approach. Specific diagnostic criteria were added, and personality disorders were placed on a separate assessment "axis," which highlighted their importance.

The changes made in DSM-III-R (American Psychiatric Association 1987) and DSM-IV (American Psychiatric Association 1994) attempted to increase the reliability and validity of the personality disorder categories by incorporating findings from a growing empirical literature. For DSM-5, an attempt was made to further increase the validity of personality disorders by developing a dimensional-categorical hybrid model, which more faithfully represents the continuous nature of personality pathology, while preserving continuity with the current clinical practice of diagnosing personality disorders as categories. Ultimately, this hybrid model was relegated to Section III of DSM-5, and the 10-category system of DSM-IV was retained for DSM-5 Section II. The Axis II designation for personality disorders has been eliminated from DSM-5, however.

Figure 25-1. Ontogeny of personality disorder classification.

Note. "──┤" indicates that category was discontinued.

Source. Adapted from Skodol AE: "Classification, Assessment, and Differential Diagnosis of Personality Disorders." Journal of Practical Psychiatry and Behavioral Health 3:261-274, 1997. Copyright 1997, Lippincott Williams & Wilkins. Used with permission.

Classification Issues

A pressing issue for the past 30 years has been whether the personality disorders (and other mental disorders) are better classified as dimensions or categories (Widiger and Samuel 2005). Addressing this question was a major motivation for undertaking DSM-5 (Kupfer et al. 2002). Do personality disorders exist along dimensions that reflect variants of personality functioning and pathological personality traits, or are they distinct categories that are qualitatively different and clearly demarcated from normal personality traits and from one another? Categorical diagnoses of personality disorders have been criticized for a number of reasons. First, excessive diagnostic co-occurrence between personality disorders has been observed in many studies: most patients with personality disorders meet criteria for more than one disorder. Second, there is considerable heterogeneity of features among patients receiving the same diagnosis. For example, given that a diagnosis of borderline personality disorder requires any 5 of 9 criteria from its poly-thetic criteria set, there are 256 different ways to meet the criteria for the disorder. The thresholds for making personality disorder diagnoses are arbitrary in that they were decided on the basis of expert consensus and not on the basis of empirical research. How different is a patient who meets 5 of 8 criteria for dependent personality disorder (the diagnostic threshold) from one who meets 4 of 8 (subthreshold)? Finally, despite the listing of 10 specific personality disorder types in DSMTV-TR, the residual category of personality disorder not otherwise specified may be the most commonly applied in clinical practice (Verheul and Widiger 2004), which suggests inadequate coverage of personality psychopathology by the DSM classification or else reflects the secondary importance accorded to personality disorders and the inordinate amount of time required to accurately diagnose these disorders with the existing criteria (e.g., 79 adult and 15 childhood [for antisocial personality disorder] criteria).

A number of different dimensional approaches to personality disorder assessment have been proposed as alternatives to DSM categories (Widiger and Simonsen 2005). The most direct approach has been to simply transform the categories into dimensions by counting criteria or rating the degree to which patients meet criteria on a continuous scale (Oldham and Skodol 2000). Another "person-centered" dimensional approach is the prototype-matching approach proposed by Westen et al. (2006). Using this approach, clinicians rate on a continuous scale the degree to which patients meet written descriptions of a prototypical patient with each personality disorder. This approach has been shown to have clinical utility and is very "clinician friendly." Other dimensional approaches rate pathological personality traits on scales of severity (Livesley and Jackson 2000), whereas still other "spectrum" models attempt to bring together so-called Axis I and Axis II disorders that seem to share fundamental underlying dimensions of psychopathology, such as internalization versus externalization (Krueger et al. 2005) or cognitive/perceptual versus affective disturbances (Siever and Davis 1991).

The most widely used dimensional approaches describe personality according to a number of broad trait factors or domains and more narrow trait dimensions or facets and assess the degree to which traits are present for a given patient. These models may more comprehensively cover both normal and pathological personality traits. Of special significance are the widely heralded "Big Five" dimensions of the Five-Factor Model of Personality: neuroticism, extraversion, openness, agreeableness, and conscientiousness (Costa and McCrae 1990). Cloninger's seven-dimension psychobiological model of temperament and character (Cloninger et al. 1993) has also generated a large body of research. The pathological personality trait model developed for DSM-5, which is based on these and other existing trait models, consists of five domains (negative affectivity, detachment, antagonism, disinhibition, and psychoticism), each comprising 3-9 (for a total of 25) trait facets (Krueger et al. 2012) (Table 25-2).

Dimensional models vary in the empirical support each has received. The genetic and phenotypic structure of the basic traits delineating personality disorders, however, has been shown to be consistent (Livesley et al. 1998). Dimensional approaches are, nonetheless, unfamiliar to those trained in a medical model of diagnosis and can appear complex to use. Categories enable clinicians to summarize patients' difficulties succinctly and facilitate communication about them.

In 2007, a Personality and Personality Disorders Work Group was appointed to consider the future of personality disorder assessment and classification in DSM-5. Key questions were articulated to inform potential revisions: What is the core definition of a personality disorder that distinguishes it from other types of psychopathology? Is personality psychopathology better described by dimensional representations of diagnostic categories or by extremes on dimensions of general personality functioning than by the categories themselves? Is a separate Axis II for personality assessment valuable? What is the clinical importance (for risk, treatment, or prognosis) of assessing personality or personality disorders in other diagnostic domains, such as mood, anxiety, substance use, or eating disorders?

Although the categorical approach to personality disorders and their specific criteria did not change in DSM-5 Section II, a new hybrid dimensional-categorical approach to personality disorder diagnosis was placed in DSM-5 Section III. For the general criteria for personality disorder (see Table 25-1), a revised personality functioning criterion—Criterion A, encompassing self functioning (identity and self-direction) and interpersonal functioning (empathy and intimacy)—was developed based on a literature review of reliable clinical measures of core impairments central to personality pathology (Bender et al. 2011) and validated as specific for semistructured interview diagnoses of personality disorders in samples of over 2,000 patients and community subjects (Morey et al. 2011). Furthermore, the moderate severity level of impairment in personality functioning, as measured by the Level of Personality Functioning Scale (Table 25-3), required for a personality disorder diagnosis in DSM-5 Section III was set empirically to maximize the ability of clinicians to identify personality disorder pathology accurately and efficiently. With a single assessment of level of personality functioning, a clinician can determine whether a full assessment for personality disorder is necessary.

The diagnostic criteria for specific DSM-5 personality disorders in the Section III model are consistently defined across disorders by typical impairments in personality functioning and by characteristic pathological personality traits (Criterion B) that have been empirically determined to be related to the personality disorders they represent. Diagnostic thresholds for both the A and the B criteria have been set empirically to minimize change in disorder prevalence (from DSM-IV) and overlap with other personality disorders and to maximize relations with psychosocial impairment. A diagnosis of personality disorder—trait specified (PD-TS), based on moderate or greater impairment in personality functioning and the presence of pathological personality traits, replaces personality disorder not otherwise specified and provides a much more informative diagnosis for patients who are not optimally described as having a specific personality disorder. A greater emphasis on personality functioning and trait-based criteria increases the stability and empirical bases of the disorders. In the "Specific Personality Disorders" section of this chapter, comparisons of DSM-5 Section II and Section III criteria are provided for two personality disorders with considerable forensic and clinical importance—antisocial and borderline personality disorders (see Tables 25-6 and 25-7, later in chapter).

Assessment Issues

The assessment of personality disorders is in some ways more complex than that of other mental disorders. It can be difficult to assess multiple aspects of personality pathology and to determine that they are distressing or impairing, of early onset, pervasive, and sufficiently enduring. Nonetheless, a personality disorder assessment is essential to the comprehensive evaluation and adequate treatment of all patients.

Comprehensiveness of Evaluation

A skilled clinical interview is the mainstay of personality disorder diagnosis and requires the clinician to be familiar with DSM criteria, take a longitudinal view, and use multiple sources of information. However, because an open-ended approach may provide insufficient information to assess all personality disorders, the addition of a self-report or semistructured (i.e., interviewer-administered) personality disorder assessment instrument may be used to augment a clinical interview. Such instruments systematically assess each personality disorder criterion with standard questions or probes. Although self-report instruments have the advantage of saving interviewer time and being free of interviewer bias, they may yield false-positive diagnoses. Semistructured interviews—which require the interviewer to use certain questions, but allow further probing—facilitate accurate diagnosis in several ways: they ensure coverage of relevant domains of personality psychopathology, allow the interviewer to attempt to differentiate traits from states, encourage clarification of contradictions or ambiguities in the patient's response, and provide the opportunity to determine that traits are relatively pervasive (i.e., by eliciting multiple examples of trait expression) rather than limited to a specific situation. Nonetheless, with or without the use of a semistructured interview, the interviewer must use his or her judgment to make the determinations and discriminations critical for personality disorder diagnosis.

State Versus Trait

The presence of another mental disorder can complicate the assessment of personality traits. For example, a person with social withdrawal, low self-esteem, and lack of motivation or energy associated with major depression might also meet criteria for avoidant or dependent personality disorder. A hypomanic person with symptoms of grandiosity or hypersexuality might appear narcissistic or histrionic. In some cases, assessment of personality disorders may need to wait until the other condition, such as severe depression or a manic episode, has subsided. However, the clinician can often differentiate personality traits from states during an episode by asking the patient to describe his or her usual personality at times not in an episode; the use of informants who have observed the patient over time with and without a disorder can also be helpful. A longitudinal study showed that personality disorders could be accurately diagnosed in the presence of major depression, in that their outcomes were almost identical to those of personality disorders diagnosed in the absence of major depression (Morey et al. 2010).

Medical Illness Versus Trait

Similarly, the interviewer must ascertain that apparent personality traits are not symptoms of a medical illness. For example, aggressive outbursts caused by a seizure disorder should not be misattributed to borderline or antisocial personality disorder, and the unusual perceptual experiences that can accompany temporal lobe epilepsy should not be misattributed to schizotypal personality disorder. On the other hand, it is possible that a personality disorder co-occurs with a medical disorder, so the possibility should not be ruled out. A thorough medical evaluation is essential if a medical causation is suspected.

Situation Versus Trait

The interviewer should also determine that personality disorder features are sufficiently pervasive—that is, not limited to only one situation or occurring in response to only one specific trigger or person. Similarly, personality traits should be relatively enduring rather than transient. Asking the patient for behavioral examples of the expression of traits can help determine that the trait is indeed present in a wide variety of situations and is expressed in many relationships. Specific behaviors, such as suicidal or other self-destructive behaviors, may only be evident at specific times or in specific situations, but the trait of impulsivity should be more persistent for a personality disorder diagnosis.

Sex and Cultural Bias

Although most research suggests that existing personality disorder criteria are relatively free of sex bias, interviewers can unknowingly allow such bias to affect their assessments. It is important, for example, that histrionic, borderline, and dependent personality disorders be assessed as carefully in men as in women and that obsessive-compulsive, antisocial, and narcissistic personality disorders be assessed as carefully in women as in men. Interviewers should also be careful to avoid cultural bias when diagnosing personality disorders, especially when evaluating such traits as emotionality, suspiciousness, or recklessness; emphasis on work and productivity; or unusual beliefs and rituals that may reflect different norms in different cultures.

Diagnosis of Personality Disorders in Children and Adolescents

Because the personalities of children and adolescents are still developing, personality disorders should be diagnosed with care in this age group. Although children and early adolescents frequently manifest significant personality disorder characteristics, it is often preferable to defer diagnoses until early adulthood, at which time a personality disorder diagnosis maybe appropriate if the features appear to be more pervasive and stable. Early diagnosis may prove to be wrong as stage-specific difficulties of adolescence resolve and as the person matures. A meta-analysis of 152 longitudinal studies of personality traits showed that change was the rule until about age 22 (Roberts and DelVecchio 2000). Nonetheless, adolescents with high levels of personality psychopathology are at greater risk for developing personality disorders in early adulthood. No minimum age for the diagnosis of a personality disorder is included in either DSM-5 Section II or Section III criteria, except for antisocial personality disorder, which has a minimum age of at least 18 years in both sections.

Clinical Significance of Personality Disorders

Personality disorders cause significant problems for those who have them. Persons with these disorders often suffer, and their relationships with others are typically problematic. They have difficulty responding flexibly and adaptively to the environment and to the changes and demands of life, and they lack resilience when under stress. Instead, their usual ways of responding tend to perpetuate and intensify their difficulties. However, individuals with personality disorders often blame others for their difficulties or even deny that they have any problems at all.

A number of studies have compared patients with personality disorders with patients with no personality disorder or with other mental disorders and have found that patients with personality disorders were more likely to be separated, divorced, or never married and to have had more unemployment, frequent job changes, or periods of disability. Studies that have examined quality of functioning found poorer social functioning or interpersonal relationships and poorer work functioning or occupational achievement and satisfaction. Among patients with personality disorders, patients with severe types, such as schizotypal and borderline, have been found to have significantly more impairment at work, in social relationships, and at leisure compared with patients with less severe types, such as obsessive-compulsive, or patients with an impairing mental disorder such as major depressive disorder in the absence of personality disorder. Even the less impaired patients with personality disorders (e.g., obsessive-compulsive), however, have moderate to severe impairment in at least one area of functioning (or a Global Assessment of Functioning rating of 60 or less) (Skodol et al. 2002). Thus, patients with specific personality disorders differ from each other not only in the degree of associated functional impairment but also in the breadth of impairment across functional domains.

Impairment in functioning in patients with personality disorders tends to be persistent even beyond apparent improvement in personality disorder psychopathology itself (Skodol et al. 2005). The persistence of impairment is understandable because personality disorder psychopathology has usually been relatively long-standing and therefore has disrupted a person's work and social development over a period of time (Roberts et al. 2003).

Personality disorders also often cause problems for others and are costly to society. They are associated with elevated rates of separation, divorce, conflict with family members and romantic partners, child custody proceedings, homelessness, high-risk sexual behavior, and perpetration of child abuse. Those with personality disorders also have increased rates of accidents; police contacts; emergency department visits; medical hospitalization and treatment utilization; violence and criminal behavior, including homicide; self-injurious behavior; attempted suicide; and completed suicide. A high percentage of individuals with criminal convictions, alcoholism, and drug abuse have a personality disorder.

Finally, personality disorders should be identified because of their implications for the development of other disorders and for treatment planning. Personality disorders often need to be a focus of treatment or, at the very least, need to be taken into account when other comorbid mental disorders are treated, because their presence often affects another disorder's prognosis and treatment response. For example, patients with depressive disorders, bipolar disorder, panic disorder, obsessive-compulsive disorder, or substance abuse often respond less well to pharmacotherapy when they have a comorbid personality disorder. The presence of a comorbid personality disorder is also associated with poor compliance with pharmacotherapy. Furthermore, personality disorders have been shown to predict the development and relapse of major depression, and individuals with a personality disorder are less likely to remit from major depression (Grilo et al. 2005; Skodol et al. 2011), substance use disorders (Hasin et al. 2011), bipolar disorder (Dunayevich et al. 2000), and generalized anxiety disorder (Yonkers et al. 2000). As most clinicians are well aware, the characteristics of patients with personality disorders are likely to be manifested in the treatment relationship regardless of whether the personality disorder is the focus of treatment. For example, some patients may be overly dependent on the clinician, others may not follow treatment recommendations, and still others may experience significant conflict about getting well. Although individuals with personality disorders tend to use psychiatric services extensively (Bender et al. 2001), they are more likely to be dissatisfied with the treatment they receive.

Etiology and Pathogenesis

What causes personality disorders remains a central and challenging question relevant to this group of complex disorders. As is the case with other psychiatric disorders, all available data suggest that personality disorders (as well as normal personality traits) result from a complex combination of, and interaction between, temperament (genetic and other biological factors) and psychological (developmental or environmental) factors. Although the degree to which genetic and environmental factors contribute to etiology may vary for different personality disorders, twin studies show that both factors are important in all of these disorders (e.g., Reichbom-Kjennerud et al. 2006). Of relevance, too, are studies showing that approximately half the observed variance in personality traits such as neuroticism, introversion, callousness, and even identity problems can be traced to genetic variation (e.g., Jang et al. 1996).

Investigation of the underlying neurobiology of personality disorders is rapidly increasing. A growing body of evidence supports the importance of various neurobiological abnormalities in persons with personality disorders—abnormalities in dopaminergic systems in individuals with schizotypal personality disorder and in the serotonin system (which appears to mediate behavioral inhibition) in individuals with impulsive aggression (Siever and Davis 2004). Of particular note is the growing interest in neurobiological correlations of disturbed interpersonal relationships within the neuropeptide system (Stanley and Siever 2010). Molecular genetic analyses have suggested associations between neuroticism and the short allele of the serotonin transporter gene 5-HTTLPR (Lesch et al. 1996) and between novelty seeking and the long allele of the dopamine receptor gene DRD4 (Benjamin et al. 1996). Although these studies have opened up a new frontier in research on personality traits and disorders, early results have generally not been replicated or the gene polymorphisms in question have been found to be less specific than originally thought (Kluger et al. 2002; Munafo et al. 2003).

Increasing numbers of studies of environmental antecedents of personality disorders, such as family environment and sexual and physical abuse, are substantiating a likely role for such factors in the development of certain disorders, particularly borderline personality disorder. Of note has been the growing literature on the relationship of disturbed early attachment to later development of personality disorders (Fonagy et al. 2007). Research in these areas is expected to continue to increase rapidly. In addition to providing information about the origins of the personality disorders, such findings are expected to open new avenues for treating these often difficult-to-treat patients.

Treatment

Significant developments in the treatment of personality disorders include the use of multiple modalities, the growth of an empirical base of the results of treatment studies, and greater optimism about treatment effectiveness. Reviews of psychotherapy outcome studies, including psychodynamic/interpersonal, cognitive-behavioral, mixed, and supportive therapies, have found that psychotherapy was associated with a significantly faster rate of recovery compared with the natural course of personality disorders (Leich-senring and Leibing 2003). Therapeutic nihilism has yielded to widespread, but very inconsistent, use of the spectrum of potentially valuable treatment modalities.

Although psychotherapy remains the mainstay of the treatment of personality disorders, the uses of pharmacotherapy are being explored as biological dimensions of personality psychopathology have been identified. For example, research has increasingly suggested that impulsivity and aggression may respond to serotonergic medications, mood instability and lability may respond to serotonergic or dopaminergic medications, and psychotic-like experiences may respond to antipsychotics.

An overview of our knowledge about the potential usefulness of the three major types of psychiatric treatment—psychotherapies, sociotherapies, and pharmacotherapies—is provided in Table 25M.

Specific Personality Disorders

A clinically oriented overview of each DSM-5 personality disorder follows. Although we do discuss each of the 10 disorders being retained in Section II of DSM-5, growing evidence suggests that some of these categories might be better represented by impairments in personality functioning and pathological personality traits, and do not meet standards for distinct disorders. Furthermore, the extensive co-occurrence among DSM personality disorders is additional evidence that the categorical representation of personality psychopathology may be an inaccurate and limited model. Therefore, we also will explain how the disorders would be represented by the alternative DSM-5 personality functioning and trait-based model. The defining features of DSM-5 Section II and Section III personality disorders are compared in Table 25-5.

Paranoid Personality Disorder

The median prevalence of paranoid personality disorder in 12 general population studies is 1.7% (Torgersen 2009). Whether it is more common among men than women is uncertain (Grant et al. 2004; Zimmerman and Coryell 1990).

Note. -=no support; ±=uncertain support; +=modestly helpful; ++=significantly helpful.

^a Includes group, family, and milieu therapies.

Clinical Features

Persons with paranoid personality disorder have a pervasive, persistent, and inappropriate mistrust of others. They are suspicious of others' motives and assume that others intend to exploit, harm, or deceive them. Thus, they may question, without justification, the loyalty or trustworthiness of friends or romantic partners, and they are reluctant to confide in others for fear the information will be used against them. Persons with paranoid personality disorder appear guarded, tense, and hyper-vigilant, and they frequently scan their environments for clues of possible attack, deception, or betrayal. They often find "evidence" of such malevolence by misinterpreting benign events (such as a glance in their direction) as demeaning or threatening. In response to perceived or actual insults or betrayals, these individuals overreact quickly, becoming excessively angry and responding with counterattacking behavior. They are unable to forgive or forget such incidents and instead bear long-term grudges against their supposed betrayers; some persons with paranoid personality disorder are extremely litigious. Whereas some individuals with this disorder can appear quietly and tensely aloof and hostile, others are overtly angry and combative. Persons with this disorder are usually socially isolated and, because of their paranoia, often have difficulties with bosses and coworkers.

In the alternative DSM-5 model for personality disorders, paranoid personality disorder would be diagnosed as PD-TS. The level of impairment in personality functioning typically would be severe or extreme, and relevant pathological personality traits would include suspiciousness and hostility.

Etiology

Paranoid personality disorder is among the least studied personality disorders. Negative childhood experiences, including physical, sexual, and emotional abuse, have been strongly associated with paranoid personality disorder (Bierer et al. 2003).

Historically, family history studies have found a greater morbid risk of paranoid personality disorder in the first-degree relatives of probands with delusional disorder than in relatives of probands with schizophrenia or medical illness. Several studies have found paranoid personality disorder in the relatives of probands with schizophrenia, but other studies have not. The heritability of paranoid personality disorder has been estimated as 0.28 in a twin study using a clinical sample (Torgersen et al. 2000) and as 0.21 or 0.66 in a twin study using a population-based sample, depending on whether interview (lower estimate) or self-report (higher) assessments were made (Kendler et al. 2006, 2007).

Note. PD-TS =personality disorder—trait specified.

Source. Adapted from American Psychiatric Association: Diagnostic and Statistical Manual of Mental Disorders, 5th Edition. Arlington, VA, American Psychiatric Association, 2013 (Copyright © 2013 American Psychiatric Association) and from Skodol AE: Manifestations, assessment, and differential diagnosis, in The American Psychiatric Publishing Textbook of Personality Disorders, 2nd Edition. Edited by Oldham JM, Skodol AE, Bender DS. Arlington, VA, American Psychiatric Publishing, in press. Used with permission.

Treatment

Because they mistrust others, persons with paranoid personality disorder usually avoid psychiatric treatment. If they do seek treatment, the therapist immediately encounters the challenge of engaging them and keeping them in treatment. This can best be accomplished by maintaining an unusually respectful, straightforward, and unobtrusive style aimed at building trust. If a rupture develops in the treatment relationship—for example, the patient accuses the therapist of some fault—it is best simply to offer a straightforward apology, if warranted, rather than to respond evasively or defensively. It is also best to avoid an overly warm style, because excessive warmth and expression of interest can intensify the patient's thoughts about the therapist's motives. A supportive individual psychotherapy that incorporates such approaches may be the best treatment for these patients. Although group treatment or cognitive-behavioral treatment aimed at anxiety management and the development of social skills can occasionally be of benefit, these patients tend to resist such approaches because of their suspiciousness, hypersensitivity to criticism, and misinterpretation of others' comments.

Although seldom studied, antipsychotic medications may sometimes be useful in the treatment of paranoid personality disorder. Patients may view such treatment with mistrust; however, these medications are more clearly indicated in the treatment of the overtly psychotic decompensations that these patients sometimes experience.

Schizoid Personality Disorder

Epidemiology

Schizoid personality disorder is one of the rarest personality disorders, occurring in less than 1% of the general population (Torgersen 2009). Schizoid personality disorder is more common among men than women (Torgersen et al. 2001; Zimmerman and Coryell 1990).

Clinical Features

Schizoid personality disorder is characterized by a profound defect in the ability to relate to others in a meaningful way. Persons with this disorder have little or no desire for relationships with others and, as a result, are extremely socially isolated. They prefer to engage in solitary, often intellectual, activities, such as computer games or puzzles, and they often create an elaborate fantasy world that they retreat into and substitute for relationships with real people. As a result of their lack of interest in relationships, they often have few or no close friends or confidants. They date infrequently, seldom marry, and have little interest in sex, and they often work at jobs requiring little interpersonal interaction (e.g., as a night watchman). In certain instances, however, someone whose internal world corresponds to this description has the appearance of carrying on a normal life with a superficial network of acquaintances. These individuals are also notable for their lack of emotional expression or affect. They usually appear cold, detached, aloof, and constricted, and they have particular discomfort with warm feelings. Few, if any, activities or experiences give them pleasure, resulting in chronic anhedonia.

In the alternative DSM-5 model for personality disorders, schizoid personality disorder would be diagnosed as PD-TS. The level of impairment in personality functioning would typically be extreme, and relevant pathological personality traits would include withdrawal, intimacy avoidance, anhedonia, and restricted affectivity.

Etiology

Schizoid personality disorder has rarely been studied. There is reason to believe that constitutional factors contribute to the childhood pattern of shyness that often precedes the disorder. Introversion (intimacy problems, inhibition), which characterizes schizoid (as well as avoidant and schizotypal) personality disorder, appears to be substantially heritable (DiLalla et al. 1996). Prenatal exposure to famine has also been shown to increase the risk for schizoid personality disorder, suggesting a role for environmental factors very early in development (Hoek et al. 1996). In two Norwegian twin studies, the heritability of schizoid personality disorder has been estimated as 0.28 (Torgersen et al. 2000) and 0.29 (Kendler et al. 2006). The best-fitting hereditary model includes both genetic and environmental factors (Kendler et al. 2007).

Treatment

Persons with schizoid personality disorder, like those with paranoid personality disorder, rarely seek treatment. They do not perceive the formation of any relationship, including a therapeutic relationship, as potentially valuable or beneficial. They may, however, occasionally seek treatment for an associated problem, such as depression, or they may be brought for treatment by others. Whereas some patients can tolerate only a supportive therapy or treatment aimed at the resolution of a crisis or associated other mental disorder, others may actually do well with insight-oriented psychotherapy aimed at bringing about a basic shift in their comfort with intimacy and affects.

Development of a therapeutic alliance may be difficult and can be facilitated by an interested and caring attitude to address the possibility of underlying neediness and by avoidance of early interpretation or confrontation. Some authors have suggested the use of so-called inanimate bridges, such as writing and artistic productions, to ease the patient into a therapy relationship. Incorporation of cognitive-behavioral approaches that encourage gradually increasing social involvement may be of value. Although many patients may be unwilling to participate in a group, group therapy may also facilitate the development of social skills and relationships.

Schizotypal Personality Disorder

Epidemiology

Schizotypal personality disorder occurs in less than 1% of the general population (Torgersen 2009). No gender difference in prevalence has been found for this disorder (Torgersen et al. 2001; Zimmerman and Coryell 1990).

Clinical Features

Schizotypal personality disorder, like schizophrenia, is characterized by positive, psychotic-like symptoms and negative, deficit-like symptoms. Persons with schizotypal personality disorder experience cognitive or perceptual distortions (positive), behave in an eccentric manner, and are socially withdrawn and anxious (negative). Common cognitive and perceptual distortions include ideas of reference, bodily illusions, and unusual telepathic and clairvoyant experiences. These distortions, which are inconsistent with subcultural norms, occur frequently and are an important and pervasive component of the person's experience. They help explain the odd and eccentric behavior characteristic of this disorder. Individuals with schizotypal personality disorder may, for example, talk to themselves in public, gesture for no apparent reason, or dress in a peculiar or unkempt fashion. Their speech is often odd and idiosyncratic—for example, unusually circumstantial, metaphorical, or vague—and their affect is constricted or inappropriate. Such a person may, for example, laugh inappropriately when discussing his or her problems.

Persons with schizotypal personality disorder are socially uncomfortable and isolated, with few friends. This isolation is often due to their eccentric cognitions and behavior, as well as their lack of desire for relationships, which stems in part from their suspiciousness of others. If they develop relationships, they tend to remain distant or may end them because of their persistent social anxiety and paranoia.

Schizotypal personality disorder is a specific personality disorder in the alternative DSM-5 model. It is characterized by specific impairments in personality functioning that are at an extreme level and by four or more of the following six pathological personality traits: cognitive and perceptual dysregulation, unusual beliefs and experiences, eccentricity, restricted affectivity, withdrawal, and suspiciousness.

Etiology

Schizotypal personality disorder is considered a schizophrenia spectrum disorder—that is, related to schizophrenia (Siever and Davis 2004). Phenomenological as well as genetic, biological, treatment, and outcome data support this link. For example, family history studies show an increased risk for schizophrenia-related disorders in relatives of schizotypal probands and, conversely, an increased risk for schizotypal personality disorder in relatives of probands with schizophrenia. Both the positive and the negative components of schizotypal personality are moderately heritable (Linney et al. 2003), although only the deficit symptoms may be genetically related to schizophrenia (Fa-nous et al. 2001; Torgersen et al. 2002). In addition, at least some forms of schizotypal personality disorder involve abnormalities of brain structure, physiology, chemistry, and functioning characteristic of schizophrenia—for example, increased cerebrospinal fluid and reduced cortical volume; temporal lobe volume reductions and dysfunctions; and abnormalities of brain physiological functions that modulate attention and inhibit sensory input, such as P50 suppression, prepulse inhibition, impaired smooth-pursuit eye movements, and poor performance on the continuous performance task. Higher cerebrospinal fluid and plasma homovanillic acid concentrations correlated with psychotic-like symptoms as well as lower concentrations correlated with deficit-like symptoms have been found in patients with schizotypal personality disorder as well as in patients with schizophrenia. Patients with schizotypal personalities have also been shown to have impaired performance on tests of executive function and other tests of visual or auditory attention, such as the Wisconsin Card Sorting Test (Grant and Berg 1993) and the backward masking task, and deficits on verbal learning and working memory tasks, attention-orienting tasks, and instrumental motor tasks. Because of this evidence, schizotypal personality disorder is classified with schizophrenia rather than with the personality disorders in the International Statistical Classification of Diseases and Related Health Problems, 10th Revision (ICD-10; World Health Organization 1992). Differences between the disorders also exist, however, particularly with respect to frontal lobe structure and functioning, which may account for the absence of overt psychosis in patients with schizotypal personality disorder (Suzuki et al. 2005). Genetic or environmental factors that promote greater frontal lobe capacity and reduced striatal dopaminergic reactivity might protect persons with schizotypal personality disorder from developing psychosis and the severe social and cognitive deterioration of chronic schizophrenia (Siever and Davis 2004).

Treatment

Because they are socially anxious and somewhat paranoid, persons with schizotypal personality disorder usually avoid psychiatric treatment. They may, however, seek such treatment—or be brought for treatment by concerned family members—when they become depressed or overtly psychotic. As with patients with paranoid personality disorder, it is difficult to establish an alliance with patients who have schizotypal personality disorder, and they are unlikely to tolerate exploratory techniques that emphasize interpretation or confrontation. A supportive relationship that counters cognitive distortions and ego-boundary problems maybe useful. This may involve an educational approach that fosters the development of social skills or encourages risktaking behavior in social situations or, if these efforts fail, encourages the development of activities with less social involvement. If the patient is willing to participate, cognitive-behavioral therapy and highly structured educational groups with a social skills focus may also be helpful.

Several studies support the usefulness of low-dose antipsychotic medications in the treatment of schizotypal personality disorder, including atypical antipsychotics such as risperidone (as found in a double-blind, placebo-controlled study; Koenigsberg et al. 2003) and olanzapine (Keshavan et al. 2004). These medications may ameliorate the anxiety and psychotic-like features associated with this disorder, and they are particularly indicated in the treatment of the more overt psychotic decompensations that these patients can experience.

Antisocial Personality Disorder

Epidemiology

Antisocial personality disorder occurs in about 1.1% of the general population (Torgersen 2009). It is much more common among men than women (Torgersen et al. 2001; Zimmerman and Coryell 1989).

Clinical Features

The central feature of antisocial personality disorder is a long-standing pattern of socially irresponsible behaviors that reflects a disregard for the rights of others. Many persons with this disorder engage in repeated unlawful acts. The more prevailing personality characteristics include a lack of interest in or concern for the feelings of others, deceitfulness, and, most notably, a lack of remorse for harm these persons may cause others. These characteristics generally make antisocial individuals fail in roles requiring fidelity (e.g., as a spouse), honesty (e.g., as an employee), or reliability (e.g., as a parent). Some antisocial persons possess a glibness and charm that can be used to seduce, outwit, and exploit others. Although most antisocial persons are indifferent to their effects on others, a notable subgroup takes sadistic pleasure in doing harm. Recent research has demonstrated that psychopathy is multidimensional and that each dimension may have a distinct developmental trajectory (Edens et al. 2006) and may be a variant of normal personality traits and behaviors (Hare and Neumann 2005). Antisocial personality syndromes are associated with high rates of substance abuse, which may contribute to the persistence of antisocial behavior over time.

Antisocial personality disorder also is a specific personality disorder in the alternative DSM-5 model. It is characterized by specific impairments in personality functioning that are at a moderate level and by six or more of the following seven pathological personality traits: manipulativeness, callousness, deceitfulness, hostility, risk taking, impulsivity, and irresponsibility. A comparison of the DSM-5 Section II and Section III criteria for antisocial personality disorder can be found in Table 25-6.

Etiology

Twin and adoption studies indicate that genetic factors predispose to the development of antisocial personality disorder (e.g., Lyons et al. 1995). Nonetheless, it is unclear how much variance is accounted for by genetic factors and whether the nature of the predisposition is relatively specific or is best conceptualized in terms of relatively nonspecific traits such as impulsivity or hostility. Conduct problems (56%), stimulus seeking (40%), and callousness (56%) are antisocial traits that have substantial heritability (Jang et al. 1996). Psychopathic traits of fearless dominance and impulsive antisociality also show significant genetic influences (Bloni-gen et al. 2005). Growing evidence indicates that impulsive and aggressive behaviors may be mediated by abnormal serotonin transporter functioning in the brain. Different psychophysiological patterns may characterize aggression, psychopathy, and antisocial behavior, however (Lorber 2004). Persons with antisocial personality disorder have reductions in whole brain volumes and in the volume of the temporal lobe in particular (Barkataki et al. 2006). Brain activation in the limbic-prefrontal circuit of the brain during fear conditioning has been shown to be deficient in psychopathic criminal offenders (Birbaumer et al. 2005). Neurocognitive impairments in spatial and memory functions have been found in adolescents with persistent antisocial behavior (Raine et al. 2005).

In addition to biological factors, the early family lives of these persons often pose severe environmental handicaps in the form of absent, inconsistent, or abusive parenting. Indeed, many family members also have significant action-oriented psychopathology, such as substance abuse or antisocial personality disorder itself. Modern behavioral genetic research is focusing on interactions between genes and the environment to explain the genesis of antisocial behavior (Moffitt 2005).

Treatment

It is clinically important to recognize antisocial personality disorder, because an uncritical acceptance of these individuals' glib or shallow statements of good intentions and collaboration can permit them to have disruptive influences on treatment teams and other patients. However, there is little evidence to suggest that this disorder can be successfully treated by usual psychiatric interventions. Of interest, nonetheless, are reports suggesting that in confined settings, such as the military or prisons, depressive and introspective concerns may surface. Under these circumstances, confrontation by peers may bring about changes in the antisocial person's social behaviors. It is also notable that some patients with antisocial personality disorder demonstrate an ability to form a therapeutic alliance with psychotherapists, which augurs well for these patients' future course. These findings contrast with the clinical tradition that emphasizes such persons' inability to learn from harmful consequences. Yet, longitudinal follow-up studies have shown that the prevalence of this disorder diminishes with age as these individuals become more aware of the social and interpersonal maladaptiveness of their most harmful social behaviors. Preventive efforts with at-risk individuals (e.g., siblings of children with conduct disorder) are also promising.

Borderline Personality Disorder

Epidemiology

Borderline personality disorder (BPD) occurs in 1.6% of the general population (Torgersen 2009) and in about 20% of hospital and clinical admissions (Gunderson and Links 2008). Although BPD is more common among women than men in clinical settings, this difference is not found in community-based studies (Grant et al. 2008; Lenzenweger et al. 2007; Torgersen et al. 2001; Zimmerman and Coryell 1990).

Clinical Features

BPD is characterized by instability and dysfunction in affective, behavioral, and interpersonal domains. Central to the psychopathology of this disorder are a severely impaired capacity for attachment (Levy et al. 2005) and predictably maladaptive behavior patterns related to separation. When patients with BPD feel cared for, held on to, and supported, depressive features (notably loneliness and emptiness) are most evident. When the threat of losing such a sustaining relationship arises, the idealized image of a beneficent caregiver is replaced by a devalued image of a cruel persecutor. This shift between idealization and devaluation is called splitting. An impending separation also evokes intense rejection or abandonment fears. To minimize these fears and to prevent the separation, rageful accusations of mistreatment and cruelty and angry self-destructive behaviors may occur. These behaviors often elicit a guilty or fearfully protective response from others.

Another central feature of this disorder is extreme affective instability that often leads to impulsive and self-destructive behaviors. These episodes are usually brief and reactive and involve extreme alternations between angry and depressed states. The experience and expression of anger can be particularly difficult for the patient with BPD. During periods of unusual stress, the individual often has dissociative experiences, holds ideas of reference, or engages in desperate impulsive acts (including substance abuse and promiscuity).

Roughly half of patients with BPD have significant remissions of their overt psychopathology within 2 years. Levels of social dysfunction, severity of childhood trauma, and persistence of substance abuse are predictive of a worse prognosis (Gunderson et al. 2006). Overall, the longer-term course of BPD may be more benign than previously thought (Gunderson et al. 2011; Zanarini et al. 2012) and may be predicted from historical, clinical, functional, and personality features (Zanarini et al. 2006). About 10% of patients with the disorder commit suicide, however (Oldham 2006).

BPD is a specific personality disorder in the alternative DSM-5 model. It is characterized by specific impairments in personality functioning that are at a severe level and by four or more of the following seven pathological personality traits: emotional lability, anxiousness, separation insecurity, depressivity, impulsivity, risk taking, and hostility. The diagnostic algorithm requires at least one of the latter three traits, because BPD has traits from both the negative affectivity and the disinhibition domains and is not typically represented by only emotional dysregulation. A comparison of the DSM-5 Section II and Section III criteria for BPD is provided in Table 25-7.

Etiology

Psychoanalytic theories have emphasized the importance of early parent-child relationships in the etiology of BPD. These theories are gradually being explored and modified by direct observations of these early dyads with long-term follow-ups. This research has generally confirmed the theories that inconsistent or absent feedback from caretakers predicts insecure attachments but that the infants themselves have traits that significantly shape the caretakers' responses (Gunderson and Lyons-Ruth 2008). A considerable body of empirical research has also documented a high frequency of traumatic early abandonment, physical abuse, and sexual abuse. These experiences have enduring traumatic effects when they occur in particularly sensitive children or in children who do not have opportunities to process the events. The lack of reliably involved attachment to caretakers during development is a source of these patients' inability to maintain stable senses of themselves or of others without ongoing contact (Bender and Skodol 2007).

Evidence of 69% overall heritability for BPD in a twin study (Torgersen et al. 2000) has mobilized efforts to identify genetic contributions to the etiology of specific borderline traits. Siever and Davis (1991) posited fundamental dimensions of affective instability and impulsive aggression underlying BPD. Livesley et al. (1993) found heritability of about 50% for borderline traits such as affective lability and insecure attachment and later for the broader domains of emotional dysregulation and dissocial behavior (Livesley et al. 1998). There is evidence of serotonergic dysfunction in the borderline trait of impulsivity. Structural and functional neuroimaging studies have shown reductions in frontal and orbitofrontal lobe volumes, altered metabolism in prefrontal brain regions, and failure of activation of these brain regions under stress. Because these brain regions are important in serotonergic function and mediate affective control, the observed deficits may be the source of the disinhibited impulses and affects characteristic of patients with BPD. Other studies have shown hyperactivity of the amygdala, which also plays a central role in emotion regulation. Patients with BPD perform poorly in multiple neurocognitive domains, particularly on functions lateralized to the right hemisphere. It is unknown, however, whether neuro-biological dysfunctions are due to genetics, pre- or postnatal factors, or adverse events during childhood or are the consequences of the disorder (Lieb et al. 2004).

All modern theories about the etiology of BPD posit a genetic vulnerability underlying poor emotional, behavioral, and interpersonal controls, recognizing that whether these vulnerabilities get expressed—that is, whether children with these vulnerabilities develop BPD—de pends on adverse childhood environments and on triggering stressors. Thus, although the specific factors in the etiology of BPD are yet to be determined, the pathways to this illness are complex and multifactorial.

Treatment

Patients with BPD are high utilizers of psychiatric outpatient, inpatient, partial hospital, and psychopharmacological treatment. Almost all modalities can be helpful. The extensive literature on the treatment of BPD universally notes the extreme difficulties that clinicians encounter with these patients. These problems derive from the patients' appeal to their treaters' wishes to rescue and to the patients' angry accusations when they perceive their treaters to have failed them. Many clinicians do not like working with these patients despite their generally good prognosis. Therapists often develop intense countertransference reactions that lead them to attempt to reparent or, conversely, to reject patients with BPD. Regardless of the treatment approach used, personal maturity and considerable clinical experience are important assets for clinicians.

Treatment of patients with BPD typically requires good case management. Essential aspects include skills in managing suicidal or self-destructive threats and behaviors, alongside calm and knowledgeable psychoeducational discussion of the diagnosis and its treatment. Such interventions frame realistic goals and a good alliance. Case management is usually accompanied by psychotherapeutic and pharmacological interventions.

Much of the early treatment literature focused on the value of intensive exploratory psychotherapies directed at modifying the basic character structure of patients with BPD. However, this literature has increasingly suggested that improvement may be related not to the acquisition of insight but to the corrective experience of developing a stable, trusting relationship with a therapist who fails to retaliate in response to these patients' angry and disruptive behaviors. Paralleling this development has been the suggestion that supportive psychotherapies or group therapies may bring about similar changes. Evidence has provided support for the effectiveness of two forms of psychoanalytic treatment. The first, mentalization-based treatment (MBT), involves a nondirective discussion of the interactions between patient and therapist (Bateman and Fonagy 1999). The second, transference-focused psychotherapy (TFP), involves more traditional interventions (Clarkin et al. 1999). Both attribute change to an improved ability to mentalize. Linehan et al. (2006) have shown that behavioral treatment consisting of a once-weekly individual and twice-weekly group regimen can effectively diminish the self-destructive behaviors and hospitalizations of patients with BPD. The success and cost-benefits of this treatment, called dialectical behavior therapy (DBT), have led to its widespread adoption and to modifications that can be used in a variety of settings. Schema-focused therapy (SFT) is another cognitive therapy that has been shown to be efficacious (Giesen-Bloo et al. 2006).

Although no one medication has been found to have dramatic or predictable effects, studies indicate that many medications may sometimes diminish specific problems such as depression, impulsivity, affective lability, or intermittent cognitive and perceptual disturbances, as well as irritability and aggressive behavior (Hollander et al. 2005). In general, the profusion of options and the often unclear benefits have encouraged polypharmacy with sometimes unfortunate side effects.

Histrionic Personality Disorder

Epidemiology

Histrionic personality disorder occurs in about 1.5% of the general population (Torgersen 2009). Individuals with histrionic personality disorder are more often women (Torgersen et al. 2001; Zimmerman and Coryell 1990).

Clinical Features

Central to histrionic personality disorder is an overconcern with attention and appearance. Persons with this disorder spend an excessive amount of time seeking attention and making themselves attractive. The desire to be found attractive may lead to inappropriately seductive or provocative dress and flirtatious behavior, and the desire for attention may lead to other flamboyant acts or self-dramatizing behavior. Persons with histrionic personality disorder also display an effusive, but labile and shallow, range of feelings. They are often overly impressionistic and given to hyperbolic descriptions of others. More generally, these persons do not attend to detail or facts, and they are reluctant or unable to make reasoned critical analyses of problems or situations. Persons with this disorder often present with complaints of depression, somatic problems of unclear origin, and a history of disappointing romantic relationships.

In the alternative DSM-5 model for personality disorders, histrionic personality disorder would be diagnosed as PD-TS. The level of impairment in personality functioning would typically be moderate, and relevant pathological personality traits would include attention seeking, emotional lability, and manipulativeness.

Etiology

Research suggests that qualities such as emotional expressiveness (Jang et al. 1996) and affective lability (Livesley et al. 1993) are heritable temperaments. From this perspective, histrionic personality disorder would consist of extreme variants of temperamental dispositions, the environmental contributions of which remain to be determined.

Treatment

Individual psychodynamic psychotherapy, including psychoanalysis, remains the cornerstone of most treatment for persons with histrionic personality disorder. This treatment is directed at increasing patients' awareness of 1) how their selfesteem is maladaptively tied to their ability to attract attention at the expense of developing other skills and 2) how their shallow relationships and emotional experiences reflect unconscious fears of real commitments. Much of this increase in awareness occurs through analysis of the here-and-now doctor-patient relationship rather than through the reconstruction of childhood experiences. Therapists should be aware that the typical idealization and eroticization that such patients bring into treatment are material for exploration, and thus therapists should be aware of countertransferential gratification.

Narcissistic Personality Disorder

Epidemiology

Narcissistic personality disorder's median prevalence in 12 community studies is 0.5% (Torgersen 2009), and it appears to be more common among men (Torgersen et al. 2001; Zimmerman and Coryell 1990).

Clinical Features

Persons with narcissistic personality disorder lack empathy for others. In relationships, narcissistic persons are often quite distant and try to sustain an illusion of self-sufficiency. This allows them to unknowingly treat others insensitively while pursuing their self-serving goals. The DSM-5 Section II definition emphasizes those people who have grandiose self-esteem, fantasies of unlimited potential, a sense of entitlement, and a need for admiration. They are vulnerable to intense reactions when their self-image is damaged. They respond with strong feelings of hurt or anger to even small slights, rejections, defeats, or criticisms. Serious depression can ensue, which is the usual precipitant for their seeking clinical help. There are other less arrogant, socially conspicuous forms of narcissistic personality disorder, however, in which a conviction of personal superiority is hidden behind social withdrawal and a facade of self-sacrifice and even humility.

Narcissistic personality disorder in the alternative DSM-5 model recognizes that self-appraisal may be either inflated or deflated and that feelings of entitlement can be either overt or covert. Typical impairments in personality functioning are at the moderate level, and relevant traits include grandiosity and attention seeking.

Etiology

Little scientific evidence is available about the pathogenesis of narcissistic personality disorder. Reconstructions based on developmental history and observations in psycho therapies indicate that this disorder develops in persons who have had their fears, failures, or dependency responded to with criticism, disdain, or neglect during their childhood years. Such experiences leave them contemptuous of such reactions in themselves and others and inexperienced in viewing others as sources of comfort and support. They develop a veneer of invulnerability and self-sufficiency that masks their underlying emptiness and constricts their capacity to feel deeply.

Treatment

Individual psychodynamic psychotherapy, including psychoanalysis, is the cornerstone of treatment for persons with narcissistic personality disorder. Following Kohut's (1971) lead, some therapists believe that the vulnerability to narcissistic injury indicates that intervention should be directed at conveying empathy for the patient's sensitivities and disappointments. This approach, in theory, allows a positive idealized transference to develop that will then be gradually disillusioned by the inevitable frustrations encountered in therapy—disillusionment that will clarify the excessive nature of the patient's reactions to frustrations and disappointments. An alternative view, explicated by Kemberg (1975), is that the vulnerability should be addressed earlier and more directly by interpretations and confrontations through which these persons will come to recognize their grandiosity and its maladaptive consequences. With either approach, the psychotherapeutic process usually requires a relatively intensive schedule over a period of years during which the therapist needs to keep foremost in his or her mind and interventions the narcissistic patient's hypersensitivity to slights and tendency to treat the therapist as someone whose worth is measured by whether he or she gratifies the patient's needs.

Avoidant Personality Disorder

Epidemiology

The prevalence of avoidant personality disorder, based on epidemiological studies, is about 1.7% (Torgersen2009). Avoidant personality disorder may be more common among women (Grant et al. 2004; Zimmerman and Coryell 1989, 1990).

Clinical Features

Persons with avoidant personality disorder experience excessive and pervasive anxiety and discomfort in social situations and in intimate relationships. Although strongly desiring relationships, these individuals avoid them because they fear being ridiculed, criticized, rejected, or humiliated. These fears reflect their low self-esteem and hypersensitivity to negative evaluation by others. When they do enter into social situations or relationships, they feel inept and are self-conscious, shy, awkward, and preoccupied with being criticized or rejected. Their lives are constricted in that they tend to avoid not only relationships but also any new activities because they fear that they will embarrass or humiliate themselves. Patients with avoidant personality disorder may engage in deliberate self-harm and experience disability in social, educational, and physical realms (Kessler 2003).

Avoidant personality disorder is a specific personality disorder in the alternative DSM-5 model. It is characterized by specific impairments in personality functioning that are at a moderate level and by three or more of the following four pathological personality traits: anxiousness (required), withdrawal, anhedonia, and intimacy avoidance.

Etiology

Research on childhood experiences of avoidant persons reveals negative childhood memories (e.g., of isolation, rejection) (Meyer and Carver 2000); poorer athletic performance, less involvement in hobbies, and less popularity (Rettew et al. 2003); and parental neglect (Joyce et al. 2003). Research in the biological sphere has implicated the importance of inborn temperament in the development of avoidant behavior. Some children as young as 21 months manifest increased physiological arousal and avoidant traits in social situations (e.g., retreat from the unfamiliar and avoidance of interaction with strangers), and this social inhibition tends to persist for many years. Family studies have demonstrated elevated rates of trait and social anxiety, as well as personality traits such as harm avoidance, in the first-degree relatives of patients with generalized social phobia, suggesting that social anxiety lies on a continuum that may be influenced by familial factors (Stein et al. 2001).

Treatment

Because of their excessive fear of rejection and criticism and their reluctance to form relationships, individuals with avoidant personality disorder may be difficult to engage in treatment. Engagement in psychotherapy may be facilitated by the therapist's use of supportive techniques, sensitivity to the patient's hypersensitivity, and gentle interpretation of the defensive use of avoidance. Although early in treatment these patients may tolerate only supportive techniques, they may eventually respond well to all kinds of psychotherapy. Clinicians should be aware of the potential for countertransference reactions such as overprotectiveness, hesitancy to adequately challenge the patient, or excessive expectations for change.

Although few data exist, it seems likely that assertiveness and social skills training may increase patients' confidence and willingness to take risks in social situations. Cognitive techniques that gently challenge patients' pathological assumptions about their sense of ineptness may also be useful. Group experiences—in particular, homogeneous supportive groups that emphasize the development of social skills—may prove useful for avoidant patients.

Promising preliminary data suggest that avoidant personality disorder may improve with treatment with monoamine oxidase inhibitors or serotonin reuptake inhibitors. Anxiolytics sometimes help patients better manage anxiety (especially severe anxiety) caused by facing previously avoided situations or trying new behaviors.

Dependent Personality Disorder

Epidemiology

Dependent personality disorder occurs in about 0.7% of the general population (Torgersen 2009) and is much more common among women (Grant et al. 2004; Torgersen et al. 2001; Zimmerman and Coryell 1989, 1990).

Clinical Features

Dependent personality disorder is characterized by an excessive need to be cared for by others, which leads to submissive and clinging behavior and excessive fears of separation. Although these individuals are able to care for themselves, they doubt their abilities and judgment, and they view others as much stronger and more capable than they are. These persons excessively rely on "powerful" others to initiate and do things for them, make their decisions, assume responsibility for their actions, and guide them through life. Low self-esteem and doubts about their effectiveness lead them to avoid positions of responsibility. Because they feel unable to function without excessive guidance, they .go to great lengths to maintain dependent relationships. They may, for example, always agree with those on whom they depend, and they tend to be excessively passive and self-sacrificing. Because they feel incapable of caring for themselves when relationships end, these individuals feel helpless and fearful. They may indiscriminately begin another relationship so that they can be provided with direction and nurturance; an unfulfilling or even abusive relationship may seem better than being on their own.

According to the alternative DSM-5 model, dependent personality disorder would be diagnosed as PD-TS. Typical impairments in personality functioning are at the moderate level, and pathological traits include submissiveness, separation insecurity, and anxiousness.

Etiology

Genetic or constitutional factors, such as innate submissiveness, may contribute to this disorder's etiology. A twin study found heritability of 45% on a scale measuring submissiveness (Jang et al. 1996). Another twin study found additive genetic effects of 25% for submissiveness, 35% for insecure attachment, and 49% for anxiousness (Livesley et al. 1993).

Cultural and social factors may also play a role in the development of dependent personality disorder. Dependency is considered not only normative but desirable in certain cultures, including in the United States. Thus, dependent personality disorder may represent an exaggerated and maladaptive variant of normal dependency; that is, it may—along with histrionic personality disorder—best be conceptualized as a "trait" disorder (i.e., occurring on a continuum with normal personality traits). It is important to recognize that to qualify for a diagnosis of dependent personality disorder, dependent traits should be so extreme that they cause significant distress or impairment in functioning.

Treatment

Patients with dependent personality disorder often enter therapy with complaints of depression or anxiety that may be precipitated by the threatened or actual loss of a dependent relationship. They often respond well to various types of individual psychotherapy. Treatment may be particularly helpful if it explores the patients' fears of independence; uses the transference to explore their dependency; and is directed toward increasing patients' self-esteem, sense of effectiveness, assertiveness, and independent functioning. These patients often seek an excessively dependent relationship with the therapist, which can lead to countertransference problems that may actually reinforce their dependence. The therapist, for example, may overprotect or be overly directive with the patient, give inappropriate reassurance and support, or prolong the treatment unnecessarily. He or she may also have excessive expectations for change or withdraw from a patient who is perceived as too needy.

Group therapy and cognitive-behavioral therapy aimed at increasing independent functioning, including assertiveness and social skills training, may be useful for some patients. If the patient is in a relationship that is maintaining and reinforcing his or her excessive dependence, couples or family therapy may be helpful.

Obsessive-Compulsive Personality Disorder

Epidemiology

Obsessive-compulsive personality disorder (OCPD) is one of the most common personality disorders in the general population, with a prevalence of about 2.1% (Torgersen 2009). OCPD is more common in men than in women (Torgersen et al. 2001; Zimmerman and Coryell 1989, 1990).

Clinical Features

Persons with OCPD are excessively orderly. They are neat, punctual, overly organized, and overly conscientious. Although these traits might be considered virtues, to qualify as OCPD, the traits must be so extreme that they cause significant distress or impairment in functioning. For example, attention to detail is so excessive or time-consuming that the point of the activity is lost, conscientiousness is so extreme that it causes rigidity and inflexibility, and perfectionism interferes with task completion. Although these individuals tend to work extremely hard, they do so at the expense of leisure activities and relationships. The most characteristic thought of persons with OCPD is "I should"—a phrase that aptly captures their overly high standards, drivenness, conscientiousness, perfectionism, rigidity, and devotion to work and duties.

These individuals also tend to be overly concerned with control—not only over the details of their own lives but also over their emotions and other people. They have difficulty expressing warm and tender feelings, often using stilted, distant phrasing that reveals little of their inner experience. They may be obstinate and reluctant to delegate tasks or to work with others unless others submit exactly to their ways of doing things, which reflects their need for interpersonal control as well as their fear of making mistakes. Their tendency to doubt and worry also manifests itself in their inability to discard worn-out or worthless objects that might be needed in the future.

OCPD is a specific personality disorder in the alternative DSM-5 model. It is characterized by specific impairments in personality functioning that are at a moderate level and by three or more of the following four pathological personality traits: rigid perfectionism (required), perseveration, intimacy avoidance, and restricted affectivity.

Etiology

Constitutional factors may play a role in the formation of OCPD. Compulsivity (37%), oppositionality (46%), restricted expression of emotion (50%; Jang et al. 1996), and intimacy problems (38%;

Livesley et al. 1993) have all been shown to be moderately heritable. An increase in serotonin activity has been associated with perfectionism and compulsivity. As is the case with other personality disorders, more empirical studies are needed to clarify this disorder's sources.

Treatment

Persons with OCPD may seem difficult to treat because of their excessive intellectualization and difficulty expressing emotion. However, these patients often respond well to psychoanalytic psychotherapy or psychoanalysis. Therapists usually need to be relatively active in treatment. They should also avoid being drawn into interesting but affectless discussions that are unlikely to have therapeutic benefit. In other words, rather than intellectualizing with patients, therapists should focus on the feelings these patients usually avoid. Power struggles that may occur in treatment offer opportunities to address the patient's excessive need for control.

Cognitive techniques may also be used to diminish the patient's excessive need for control and perfection. Although patients may resist group treatment because of their need for control, dynamically oriented groups that focus on feelings may provide insight and increase patients' comfort with exploring and expressing new affects.

Other Personality Disorders

The diagnosis personality change due to another medical condition is assigned when a persistent personality disturbance that represents a change in an individual's previous characteristic personality pattern occurs as a result of another (mental disorders are considered medical conditions in DSM-5) medical condition. The clinical history, physical examination, and/or laboratory tests must provide evidence for a direct pathophysiological relationship between the other medical condition and the personality disturbance. In addition, the personality disturbance must 1) cause significant distress or impairment in social, occupational, or other important areas of functioning; 2) not be better explained by another mental disorder; and 3) not occur exclusively during the course of a delirium. The predominant feature(s) of the personality change can be specified by "type": labile, disinhibited, aggressive, apathetic, paranoid, other, combined (i.e., more than one feature predominates), or unspecified. Using the Section III model, any of the 25 pathological personality traits can be used to describe the personality features in such a case, alone or in combination.

When symptoms characteristic of a personality disorder are present but do not meet criteria for one of the 10 personality disorders in Section II of DSM-5, a diagnosis of other specified personality disorder or unspecified personality disorder can be made. These diagnoses replace personality disorder not otherwise specified (PD-NOS) from previous DSM editions. An example would be a case that had features of a number of personality disorders but did not meet the full criteria for any one ("mixed personality disorder") or that had features of a clinically recognized personality disorder that is not included in DSM-5 (e.g., passive-aggressive or depressive personality disorder). When the clinician can specify the reason that the presentation does not correspond to one of the 10 personality disorders, the "other specified" category is used. If the clinician chooses not to state or cannot further specify the reason (e.g., has limited clinical information beyond what is necessary for a personality disorder diagnosis according to the general criteria [see Table 25-1]), the "unspecified" category is used. For the Section III Alternative DSM-5 Model for Personality Disorders, an individual who meets the general criteria for a personality disorder (see Table 25-1) but does not qualify for one of the six specified categories would be assigned the diagnosis personality disorder—trait specified (PD-TS), and the pathological personality traits would be listed. For example, an individual who has features of borderline personality disorder restricted to the negative affectivity domain would receive the diagnosis "PD-TS with emotional lability, depressivity, and separation insecurity." In the case of passive-aggressive personality disorder, the listed traits might include submissiveness and hostility; in the case of depressive personality disorder, the listed traits might include depressivity, anxiousness, and anhedonia. The Section III model provides considerable flexibility in describing the myriad presentations of personality pathology that do not fit one of the specific types.

Conclusion

Clinical interest and research in the personality disorders have grown enormously since 1980, when these disorders were put on a separate axis in DSM-III. The ensuing period has brought to light more specific and effective treatment strategies and a better understanding of these disorders' prognosis and etiology. Even more dramatic than the knowledge gained is the heightened awareness of the clinical impact and potential research significance of personality disorders and the new and more informed questions that this awareness has generated. It will be essential that a focus on personality disorders not be lost as a result of the elimination of Axis II in DSM-5. Many challenges remain, including further clarification of the boundaries between personality disorders and both normal personality traits and other mental disorders; the discovery of biogenetic bases for aspects of personality functioning, such as the self and traits that underlie disorders; and the development of even more effective treatments. There is good reason to believe that with continued inquiry by clinical and basic-science investigators, the classification of personality disorders will continue to change so that it becomes even more tightly linked to etiology, treatment, and outcome.

Key Clinical Points

• Personality disorders are common in clinical settings and in the community.
• Personality disorders can be challenging to diagnose.
• Personality disorders cause significant problems for those who have them and for others, and are costly to society.
• Most personality disorders are treatable, but personality disorders often complicate the treatment of other mental disorders.
• Although personality disorders are defined in Section II of DSM-5 exactly as they were in DSM-IV, DSM-5 Section III provides an alternative model of personality disorders with the promise of greater clinical utility.

References

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Suggested Readings

American Psychiatric Association: Practice guideline for the treatment of patients with borderline personality disorder. Am J Psychiatry 158(suppl):l-52, 2001

American Psychiatric Association: Practice Guidelines for the Treatment of Psychiatric Disorders: Compendium 2006. Washington, DC, American Psychiatric Publishing, 2006 Practice guidelines available at: http://psychiatryonline.org/guide-lines.aspx.

Bateman A, Fonagy P: Mentalization-Based Treatment for Borderline Personality Disorder: A Practical Guide. New York, Oxford University Press, 2006

Beck AT, Freeman A, Davis DD, et al: Cognitive Therapy of Personality Disorders, 2nd Edition. New York, Guilford, 2004

Clarkin JF, Fonagy P, Gabbard GO: Psychodynamic Psychotherapy for Personality Disorders: A Clinical Handbook. Washington, DC, American Psychiatric Publishing, 2010

Gabbard GO: Gabbard's Treatment of Psychiatric Disorders, 4th Edition. Washington, DC, American Psychiatric Publishing, 2007

Gunderson JG, Links PS: Borderline Personality Disorder: A Clinical Guide. Washington, DC, American Psychiatric Publishing, 2008

Oldham JM, Skodol AE, Bender DS (eds): The American Psychiatric Publishing Textbook of Personality Disorders. Washington, DC, American Psychiatric Publishing, 2005

Oldham JM, Skodol AE, Bender DS (eds): The American Psychiatric Publishing Textbook of Personality Disorders, 2nd Edition. Washington, DC, American Psychiatric Publishing, in press

Oldham JM, Skodol AE, Bender DS (eds): Essentials of Personality Disorders. Washington, DC, American Psychiatric Publishing, 2009

Rush AJ Jr, First MB, Blacker D (eds): Handbook of Psychiatric Measures, 2nd Edition. Washington, DC, American Psychiatric Publishing, 2007

Widiger TA, Costa PT Jr (eds): Personality Disorders and the Five-Factor Model of Personality, 3rd Edition. Washington, DC, American Psychological Association, 2012

Zanarini M: Role of Sexual Abuse in the Etiology of Borderline Personality Disorder. Washington, DC, American Psychiatric Press, 1997