Abnormal Psychology

Personality Disorders 573

(Blais & Norman, 1997; Kupfer, First, & Regier, 2002). For instance, schizoid and

schizotypal personality disorders share a number of features, including a pattern of

poor social skills and abilities and a small number of social contacts. Similarly, his-

trionic and narcissistic personality disorders share a pattern of grandiosity and the

desire to be the center of attention.

In addition, some personality disorders are not clearly distinct from related Axis

I disorders (Widiger & Trull, 2007). The diagnostic criteria for avoidant personality

disorder, for example, overlap considerably with those for social phobia, as we’ll

discuss in detail in the section on avoidant personality disorder. Similarly, critics

point out that the general criteria for personality disorders (Table 13.1, Criteria A

through D) could apply to some Axis I disorders such as dysthymia and schizophre-

nia (Oldham, 2005).

The process by which the DSM-IV-TR criteria were determined is another target

of criticism. The minimum number of symptoms needed to make a diagnosis, as well

as the specifi c criteria, aren’t necessarily supported by research results (Widiger &

Trull, 2007). Moreover, different personality disorders require different numbers of

symptoms and different levels of impairment (Livesley, 2001; Skodol, 2005; Tyrer &

Johnson, 1996; Westen & Shedler, 2000).

The high comorbidity among personality disorders invites another criticism: that

the specifi c personality disorders do not capture the appropriate underlying problems,

and so clinicians must use more than one diagnosis to describe the types of problems

exhibited by patients (Widiger & Mullins-Sweatt, 2005). In fact, the most frequently

diagnosed personality disorder is personality disorder not otherwise specifi ed, which

is often diagnosed along with an additional personality disorder (Verheul, Bartak, &

Widiger, 2007; Verheul & Widiger, 2004). As with other categories of disorders, the

not otherwise specifi ed diagnosis is used when a patient’s symptoms cause distress

or impair functioning but do not fi t the criteria for any of the disorders within the

relevant category—in this case, one of the ten specifi c personality disorders.

Prevalence

• Researchers estimate that up to 14% of Americans will have at least one personality disorder
  over the course of their lives (Grant, Hasin, et al., 2004; Lenzenweger, 2006; Samuels et al.,
  2002; Torgersen et al., 2001).
  Comorbidity


• Up to 75% of those with a personality disorder will also be diagnosed with an Axis I disorder
  (Dolan-Sewell, Krueger, & Shea, 2001; Lenzenweger, 2006).


• Common comorbid disorders from Axis I are mood disorders, anxiety disorders, and
  substance-related disorders (Grant, Stinson, et al., 2004; Johnson, Cohen, Kasen, & Brook,
  2006a; Lenzenweger, 2006).


• Around 50% of people with a personality disorder will be diagnosed with at least one other
  personality disorder (Skodol, 2005).
  Onset


• The DSM-IV-TR diagnostic criteria require that symptoms arise by young adulthood.


• For one personality disorder—antisocial personality disorder—a diagnostic criterion requires
  that symptoms arise before age 15.
  Course


• Symptoms of personality disorders are often relatively stable, but they may fl uctuate or
  improve as people go through adulthood.
  Gender Differences


• Specifi c personality disorders have gender differences in prevalence, but there is no such
  difference across all personality disorders.
  Source: Unless otherwise noted, the source is American Psychiatric Association, 2000.

Table 13.3 • An Overview: Personality Disorder Facts at a Glance