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Overview of Personality Disorders


Mark Zimmerman

, MD, Rhode Island Hospital

Last review/revision May 2021 | Modified Sep 2022
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Personality disorders in general are pervasive, enduring patterns of thinking, perceiving, reacting, and relating that cause significant distress or functional impairment. Personality disorders vary significantly in their manifestations, but all are believed to be caused by a combination of genetic and environmental factors. Many gradually become less severe with age, but certain traits may persist to some degree after the acute symptoms that prompted the diagnosis of a disorder abate. Diagnosis is clinical. Treatment is with psychosocial therapies and sometimes drug therapy.

Personality traits represent patterns of thinking, perceiving, reacting, and relating that are relatively stable over time.

Personality disorders exist when these traits become so pronounced, rigid, and maladaptive that they impair work and/or interpersonal functioning. These social maladaptations can cause significant distress in people with personality disorders and in those around them. For people with personality disorders (unlike many others who seek counseling), the distress caused by the consequences of their socially maladaptive behaviors is usually the reason they seek treatment, rather than any discomfort with their own thoughts and feelings. Thus, clinicians must initially help patients see that their personality traits are the root of the problem.

Personality disorders usually start to become evident during late adolescence or early adulthood, although sometimes signs are apparent earlier (during childhood). Traits and symptoms vary considerably in how long they persist; many resolve with time.

The Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) lists 10 types of personality disorders Types of Personality Disorders Personality disorders in general are pervasive, enduring patterns of thinking, perceiving, reacting, and relating that cause significant distress or functional impairment. Personality disorders... read more , although most patients who meet criteria for one type also meet criteria for one or more others. Some types (eg, antisocial Antisocial Personality Disorder (ASPD) Antisocial personality disorder is characterized by a pervasive pattern of disregard for consequences and for the rights of others. Diagnosis is by clinical criteria. Treatment may include cognitive-behavioral... read more , borderline Borderline Personality Disorder (BPD) Borderline personality disorder is characterized by a pervasive pattern of instability and hypersensitivity in interpersonal relationships, instability in self-image, extreme mood fluctuations... read more ) tend to lessen or resolve as people age; others (eg, obsessive-compulsive Obsessive-Compulsive Personality Disorder (OCPD) Obsessive-compulsive personality disorder is characterized by a pervasive preoccupation with orderliness, perfectionism, and control (with no room for flexibility) that ultimately slows or interferes... read more , schizotypal Schizotypal Personality Disorder (STPD) Schizotypal personality disorder is characterized by a pervasive pattern of intense discomfort with and reduced capacity for close relationships, by distorted cognition and perceptions, and... read more ) are less likely to do so.

About 10% of the general population and up to half of psychiatric patients in hospital units and clinics have a personality disorder. Overall, there are no clear distinctions in terms of sex, socioeconomic class, and race. However, in antisocial personality disorder, men outnumber women 6:1. In borderline personality disorder, women outnumber men 3:1 (but only in clinical settings, not in the general population).

For most personality disorders, levels of heritability are about 50%, which is similar to or higher than that of many other major psychiatric disorders. This degree of heritability argues against the common assumption that personality disorders are character flaws primarily shaped by an adverse environment.

Types of Personality Disorders

DSM-5 groups the 10 types of personality disorders into 3 clusters (A, B, and C), based on similar characteristics. However, the clinical usefulness of these clusters has not been established.

Cluster A is characterized by appearing odd or eccentric. It includes the following personality disorders with their distinguishing features:

Overview of Cluster A Personality Disorders

Cluster B is characterized by appearing dramatic, emotional, or erratic. It includes the following personality disorders with their distinguishing features:

Overview of Cluster B Personality Disorders

Cluster C is characterized by appearing anxious or fearful. It includes the following personality disorders with their distinguishing features:

Overview of Cluster C Personality Disorders

Symptoms and Signs of Personality Disorders

According to DSM-5, personality disorders are primarily problems with

  • Self-identity

  • Interpersonal functioning

Self-identity problems may manifest as an unstable self-image (eg, people fluctuate between seeing themselves as kind or cruel) or as inconsistencies in values, goals, and appearance (eg, people are deeply religious while in church but profane and disrespectful elsewhere).

Interpersonal functioning problems typically manifest as failing to develop or sustain close relationships and/or being insensitive to others (eg, unable to empathize).

People with personality disorders often seem inconsistent, confusing, and frustrating to people around them (including clinicians). These people may have difficulty knowing the boundaries between themselves and others. Their self-esteem may be inappropriately high or low. They may have inconsistent, detached, overemotional, abusive, or irresponsible styles of parenting, which can lead to physical and mental problems in their spouse and/or children.

People with personality disorders may not recognize that they have problems.

Diagnosis of Personality Disorders

  • Clinical criteria (DSM-5)

Personality disorders are underdiagnosed. When people with personality disorders seek treatment, their chief complaints are often of depression or anxiety rather than of the manifestations of their personality disorder. Once clinicians suspect a personality disorder, they evaluate cognitive, affective, interpersonal, and behavioral tendencies using specific diagnostic criteria. More sophisticated and empirically rigorous diagnostic tools are available for more specialized and academic clinicians.

Diagnosis of a personality disorder requires the following:

  • A persistent, inflexible, pervasive pattern of maladaptive traits involving 2 of the following: cognition (ways or perceiving and interpreting self, others, and events), affectivity, interpersonal functioning, and impulse control

  • Significant distress or impaired functioning resulting from the maladaptive pattern

  • Relative stability and early onset (traced back to at least adolescence or early adulthood) of the pattern

For a personality disorder to be diagnosed in patients < 18 years, the pattern must have been present for 1 year, except for antisocial personality disorders, which cannot be diagnosed in patients < 18 years.

Because many patients with a personality disorder lack insight into their condition, clinicians may need to obtain history from clinicians who have treated these patients previously, other practitioners, family members, friends, or others who have contact with them.

Treatment of Personality Disorders

  • Psychotherapy

The gold standard of treatment for personality disorders is psychotherapy. Both individual and group psychotherapy are effective for many of these disorders if the patient is seeking treatment and is motivated to change.

Typically, personality disorders are not very responsive to drugs, although some drugs can effectively target specific symptoms (eg, depression, anxiety).

Disorders that often coexist with personality disorders (eg, depressive disorders Overview of Mood Disorders Mood disorders are emotional disturbances consisting of prolonged periods of excessive sadness, excessive joyousness, or both. Mood disorders can occur in children and adolescents (see Depressive... read more , anxiety Overview of Anxiety Disorders Everyone periodically experiences fear and anxiety. Fear is an emotional, physical, and behavioral response to an immediately recognizable external threat (eg, an intruder, a car spinning on... read more , substance-related Substance Use Disorders Substance use disorders involve a pathologic pattern of behaviors in which patients continue to use a substance despite experiencing significant problems related to its use. Diagnosis of substance... read more disorders, somatic symptom Somatic Symptom Disorder Somatic symptom disorder is characterized by multiple persistent physical complaints that are associated with excessive and maladaptive thoughts, feelings, and behaviors related to those symptoms... read more disorders, and eating disorders Introduction to Eating Disorders Eating disorders involve a persistent disturbance of eating or of behavior related to eating that Alters consumption or absorption of food Significantly impairs physical health and/or psychosocial... read more ) can make treatment challenging, lengthening time to remission, increasing risk of relapse, and decreasing response to otherwise effective treatment. For treatment recommendations for each disorder, see table Treatment of Personality Disorders Treatment of Personality Disorders Treatment of Personality Disorders .


General principles of treatment

In general, treatment of personality disorders aims to

  • Reduce subjective distress

  • Enable patients to understand that their problems are internal to themselves

  • Decrease significantly maladaptive and socially undesirable behaviors

  • Modify problematic personality traits

Reducing subjective distress (eg, anxiety, depression) is the first goal. These symptoms often respond to increased psychosocial support, which often includes moving the patient out of highly stressful situations or relationships. Drug therapy may also help relieve stress. Reduced stress makes treating the underlying personality disorder easier.

An effort to enable patients to see that their problems are internal should be made early. Patients need to understand that their problems with work or relationships are caused by their problematic ways of relating to the world (eg, to tasks, to authority, or in intimate relationships). Achieving such understanding requires a substantial amount of time, patience, and commitment on the part of a clinician. Clinicians also need a basic understanding of the patient’s areas of emotional sensitivity and usual ways of coping. Family members and friends can help identify problems of which patients and clinicians would otherwise be unaware.

Maladaptive and undesirable behaviors (eg, recklessness, social isolation, lack of assertiveness, temper outbursts) should be dealt with quickly to minimize ongoing damage to jobs and relationships. Behavioral change is most important for patients with the following personality disorders:

Behavior can typically be improved within months by group therapy and behavior modification; limits on behavior must often be established and enforced. Sometimes patients are treated in a day hospital or residential setting. Self-help groups or family therapy can also help change socially undesirable behaviors. Because family members and friends can act in ways that either reinforce or diminish the patient’s problematic behavior or thoughts, their involvement is helpful; with coaching, they can be allies in treatment.

Modifying problematic personality traits (eg, dependency, distrust, arrogance, manipulativeness) takes a long time—typically > 1 year. The cornerstone for effecting such change is

  • Individual psychotherapy

During therapy, clinicians try to identify interpersonal problems as they occur in the patient's life. Clinicians then help patients understand how these problems are related to their personality traits and provide skills training to develop new, better ways of interacting. Typically, clinicians must repeatedly point out the undesirable behaviors and their consequences before patients become aware of them. This strategy can help patients change their maladaptive behaviors and mistaken beliefs. Although clinicians should act with sensitivity, they should be aware that kindness and sensible advice by themselves do not change personality disorders.

Key Points

  • Personality disorders involve rigid, maladaptive personality traits that are marked enough to cause significant distress or to impair work and/or interpersonal functioning.

  • Treatments become effective only after patients see that their problems are within themselves, not just externally caused.

  • Psychosocial therapies are the main treatment.

  • Drugs help control specific symptoms only in selected cases—eg, to control significant anxiety, angry outbursts, and depression.

  • Personality disorders are often resistant to change, but many gradually become less severe over time.

More Information

The following is an English-language resource that may be useful. Please note that THE MANUAL is not responsible for the content of this resource.

  • Skodol AE, Bender DS, Oldham JM: Personality pathology and personality disorders. In American Psychiatric Association Publishing Textbook of Psychiatry, 7th Edition, edited by LW Roberts, Washington, DC, 2019, pp. 711-748.

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