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Personality Disorders


  • Personality disorders represent “an enduring pattern of inner experience and behavior that deviates markedly from the expectations of the individual’s culture” per the Diagnostic and Statistical Manual on Mental Disorders, Fifth Edition (DSM-5). These patterns tend to be fixed and consistent across situations and leads to distress or impairment. Additional data on borderline personality disorder is included on this page.
  • Borderline personality disorder is a serious mental disorder marked by a pattern of instability in moods, behavior, self-image, and functioning. These experiences often result in impulsive actions and unstable relationships. A person with borderline personality disorder may experience intense episodes of anger, depression, and anxiety that may last from only a few hours to days. Additional information about borderline personality disorder can be found on the NIMH Health Topics page on Borderline Personality Disorder.

Prevalence of Personality Disorders in Adults

  • Based on diagnostic interview data from the National Comorbidity Study Replication (NCS-R), Figure 1 shows the past year prevalence of U.S. adults aged 18 and older with personality disorders.1
    • The prevalence of any personality disorder was 9.1% and borderline personality disorder was 1.4%.
    • Sex and race were not found to be associated with the prevalence of personality disorders.

Figure 1

Past Year Prevalence of Personality Disorders Among Adults (2001-2003)
Any Personality Disorder 9.1
Borderline Personality Disorder 1.4

Co-morbidity with Other Mental Disorders in Adults

  • Based on diagnostic interview data from the NCS-R, Table 1 shows the past year co-morbidity of personality disorders with core mental disorders in DSM-IV.1
  • A large proportion of people with past year personality disorders also had one or more other mental disorder(s) (84.5%).1

Table 1

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Past Year Co-morbidity of Personality Disorders with Other Core Disorders
Among U.S. Adults
Data from National Comorbidity Survey Replication (NCS-R) 1
Any Personality Disorder (%) Borderline Personality Disorder (%)
Any Anxiety Disorder 52.4 60.5
Any Mood Disorder 24.1 34.3
Any Impulse Control Disorder 23.2 49.0
Any Substance Use Disorder 22.6 38.2
Any Disorder 67.0 84.5

Treatment for Personality Disorders in Adults

  • Based on diagnostic interview data from the NCS-R, Table 2 shows the past year treatment of personality disorders among U.S. adults 18 and older.1
  • Over a third (39.0%) of respondents with any personality disorder and 42.4% of respondents with borderline personality disorder reported receiving mental health treatment at some time in the past 12 months.

Table 2

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Past Year Treatment of Personality Disorders Among U.S. Adults
Data from National Comorbidity Survey Replication (NCS-R) 1
Any Personality Disorder (%) Borderline Personality Disorder (%)
Received Any Treatment 39.0 42.4

Data Sources


  1. Lenzenweger MF, Lane MC, Loranger AW, Kessler RC. DSM-IV personality disorders in the National Comorbidity Survey Replication. Biol Psychiatry. 2007 Sep 15;62(6):553-64. PMID: 17217923 

Statistical Methods and Measurement Caveats

National Comorbidity Survey Replication (NCS-R)

Diagnostic Assessment and Population:

  • The NCS-R is a nationally representative, face-to-face, household survey conducted between February 2001 and April 2003 with a response rate of 70.9%. DSM-IV mental disorders were assessed using a modified version of the fully structured World Health Organization Composite International Diagnostic Interview (WMH-CIDI), a fully structured lay-administered diagnostic interview that generates both International Classification of Diseases, 10th Revision, and DSM-IV diagnoses. The DSM-IV criteria were used here. Participants for the main interview totaled 9,282 English-speaking, non-institutionalized, civilian respondents. Any personality disorder and borderline personality disorder were assessed using screening questions from the International Personality Disorder Examination (IPDE) in the full NCS-R sample of 5,692 adults, aged 18 and older. The NCS-R was led by Harvard University.

Survey Non-response:

  • In 2001-2002, non-response was 29.1% of primary respondents and 19.6% of secondary respondents.
  • Reasons for non-response to interviewing include: refusal to participate (7.3% of primary, 6.3% of secondary); respondent was reluctant- too busy but did not refuse (17.7% of primary, 11.6% of secondary); circumstantial, such as intellectual developmental disability or overseas work assignment (2.0% of primary, 1.7% of secondary); and household units that were never contacted (2.0%).
  • For more information, see PMID: 15297905 .