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Psychiatric-Mental Health Nursing

18.2 Cluster Disorders (A, B, C)

Psychiatric-Mental Health Nursing18.2 Cluster Disorders (A, B, C)

Learning Objectives

By the end of this section, you will be able to:

  • Outline the key features related to different types of cluster A personality disorders
  • Outline the key features related to different types of cluster B personality disorders
  • Outline the key features related to different types of cluster C personality disorders

Personality disorders can be grouped into three distinct clusters, each characterized by its own unique features and patterns. These clusters provide a framework for understanding the different types of personality disorders and the challenges associated with them (Fariba et al., 2023).

Cluster A comprises the “odd and eccentric” personalities (APA, 2022a). People in this cluster often exhibit peculiar behaviors, unconventional thoughts, and may come across as distant or detached. They may have difficulties forming and maintaining social relationships and display patterns of suspicion, magical thinking, or idiosyncratic beliefs.

Cluster B consists of the “dramatic, emotional, and erratic” personalities. Individuals within this cluster tend to exhibit intense emotions, have unpredictable and turbulent relationships, and display attention-seeking behaviors. They may struggle with emotional regulation, have a fragile self-image, and exhibit impulsive or manipulative tendencies.

Cluster C encompasses the “anxious and fearful” personalities. Individuals in this cluster often experience high levels of anxiety, fear, and a strong desire for security. They may exhibit patterns of avoidance, dependency, or perfectionism as a way to manage their anxieties and seek reassurance.

Understanding these three clusters helps nurses recognize and categorize the diverse presentations of personality disorders. While each cluster shares certain characteristics, it is important to remember that individuals within these clusters can still have unique experiences and variations in symptom severity.

Cluster A

Cluster A personality disorders include paranoid personality disorder, schizoid personality disorder, and schizotypal personality disorder (APA, 2022a). Cluster A is characterized by eccentric, odd, or peculiar behavior, thinking, and beliefs. Individuals with these disorders often struggle socially. They can often appear distrustful of and detached from others (Figure 18.2).

Chart of Cluster A Personality Disorder traits: Paranoid, Schizoid, and Schizotypal.
Figure 18.2 Cluster A personality disorders have similar symptoms. (attribution: Copyright Rice University, OpenStax, under CC BY 4.0 license)


Paranoid personality disorder is characterized by a pervasive pattern of distrust and suspicion of others (APA, 2022a). It is diagnosed in individuals with four or more of the following characteristics beginning in early adulthood:

  • suspects that others are abusing, hurting, or misleading them without any proof
  • is preoccupied with unjustified doubts about the loyalty or trustworthiness of friends or associates
  • is hesitant to share any information with others due to unjustified fear that the information will be used against them
  • attributes hidden, often threatening meanings to harmless remarks or events
  • is unforgiving and persistently holds grudges
  • is quick to perceives attacks on their self or character or reputation that are not obvious to others and tends to react angrily
  • has persistent, unfounded suspicions regarding the fidelity of their spouse or sexual partner

People with this condition believe that others will exploit, injure, or deceive them, even when no evidence exists to support this belief. They are preoccupied with the idea of loyalty from friends and associates and are often highly suspicious, even when these people show supportive behavior.


Schizoid personality disorder is characterized by a pattern of detachment from social relationships and a limited range of emotional expression (APA, 2022a). It is diagnosed in individuals with four or more of the following characteristics beginning in early adulthood:

  • lack of interest in and desire for close relationships, including family relationships
  • tendency to choose solitary occupations or hobbies
  • lack of desire for or enjoyment of sexual experiences
  • seeming enjoyment of few, if any, activities
  • lack of close friends or confidants other than immediate family
  • indifference to praise or criticism from others
  • limited range of emotional expression, appearing detached or having a flattened affect


Schizotypal personality disorder is a mental health condition characterized by odd or eccentric behavior, unusual beliefs or magical thinking, social and interpersonal difficulties, and a tendency toward perceptual and cognitive distortions (APA, 2022a). It is diagnosed in individuals with five or more of the following characteristics beginning in early adulthood:

  • The false belief that coincidental events relate to oneself, called ideas of reference. For example, a person shopping in a store sees two strangers laughing and believes that they are laughing at them, when, in reality, the other two people do not even notice them.
  • Strange beliefs or magical thinking that influence behavior and are not consistent with cultural norms. The idea that one can influence the outcome of specific events by doing something that has no bearing on the circumstances is called magical thinking. For example, a person watching a baseball game exhibits magical thinking when believing that holding the remote control in a certain position caused their favorite player to hit a home run.
  • Unusual perceptual experiences, including bodily illusions. A body illusion refers to a discrepancy between the actual physical characteristics of the body and the way it is perceived by an individual. For example, the client may report feeling as if their body is not their own.
  • Peculiar thinking and speech.
  • Paranoid ideation, feeling suspicious of others or like people are “out to get” them.
  • Emotional expressions that are flat, inappropriate, or lacking in range, such as a blunted or restricted affect.
  • Behaviors or appearance that is considered eccentric, peculiar, or unusual.
  • Few close relationships outside of immediate family members and a preference for solitary activities.
  • Extreme anxiety and discomfort in social situations.

Cluster B

Cluster B personality disorders include antisocial, borderline, histrionic, and narcissistic personality disorders (Figure 18.3). Cluster B personality disorders are characterized by dramatic, overly emotional, or unpredictable thinking or behavior. These individuals may also have a history of unstable relationships.

Chart explaining Cluster B Personality Disorders: Antisocial, Borderline, Histrionic, and Narcissistic.
Figure 18.3 Cluster B personality disorders involve excessive emotion. (attribution: Copyright Rice University, OpenStax, under CC BY 4.0 license)


The essential feature of antisocial personality disorder is a pervasive pattern of disregard for, and violation of, the rights of others that begins in childhood or early adolescence and continues into adulthood (Mayo Foundation for Medical Education and Research, 2023). In childhood or adolescence, symptoms may appear in the form of aggression, dishonesty, theft, property destruction, and disregard for rules. Antisocial personality is not diagnosed in clients before the age of eighteen, however, because their personalities are still developing. A person needs to be eighteen years or older to be diagnosed with antisocial personality disorder, but symptoms usually begin in adolescence. Typically, adolescents will be diagnosed with conduct disorder then antisocial personality disorder when they turn eighteen. Antisocial personality disorder is diagnosed in individuals with three or more of the following characteristics (APA, 2022a):

  • failure to conform to social norms and laws; repeatedly engaging in illegal activities
  • deceitfulness, lying, or using aliases for personal gain or pleasure
  • impulsivity or failure to plan ahead
  • irritability and aggressiveness, often resulting in physical violence and assaults
  • reckless disregard for the safety of self or others
  • consistent irresponsibility, such as neglecting work or financial obligations
  • lack of remorse, indifference, or rationalizing behavior that harms or exploits others


The central features of borderline personality disorder are a pervasive pattern of instability of interpersonal relationships, self-image, and affects, and marked impulsivity that begins by early adulthood and is present in a variety of contexts. It is diagnosed in individuals with five or more of the following characteristics beginning in early adulthood (APA, 2022a):

  • desperate attempts to avoid real or imagined abandonment
  • a history of unstable and intense personal relationships that are characterized by splitting, or the alternating between extremes of idealization and devaluation of one’s partner
  • identity disturbance, characterized by an unstable self-image or sense of self
  • impulsivity in at least two potentially self-damaging areas, such as reckless spending, substance misuse, reckless driving, binge eating, or engaging in unprotected sex
  • recurrent suicidal behaviors, gestures, or threats or self-harming behaviors
  • emotional instability due to marked reactivity of mood, such as intense and rapidly shifting emotions that may only last a few hours
  • chronic feelings of emptiness or boredom
  • inappropriate, intense anger or difficulty controlling anger, often resulting in frequent displays of temper, physical fights, or verbal aggression
  • transient, stress-related paranoid thoughts or severe dissociative symptoms (dissociative symptoms include the experience of detachment from oneself or reality) during times of extreme stress


The essential features of histrionic personality disorder are a pattern of pervasive and excessive emotionality and attention-seeking behavior that begins by early adulthood and is present in a variety of contexts. It is diagnosed in individuals with five or more of the following characteristics (APA, 2022a):

  • discomfort in situations where one is not the center of attention, often seeking to be the focus of others through exaggerated behaviors and emotions
  • interaction with others that is characterized by inappropriate, seductive, or provocative behavior
  • rapidly shifting and shallow expression of emotion
  • use of physical appearance to draw attention to oneself, often with excessive attention to detail or exaggerated sexuality
  • speech that is lacking in detail and lacking in substance
  • theatrical and exaggerated emotional expression, often with rapidly shifting and exaggerated emotions
  • suggestible, easily influenced by others or circumstances, with a tendency to consider relationships to be more intimate than they actually are


Narcissistic personality disorder is characterized by an inflated sense of self-importance, a constant need for admiration and attention, and a lack of empathy for others. It is diagnosed in individuals beginning in early adulthood with five or more of the following characteristics (APA, 2022a):

  • has a feeling of grandiosity—an exaggerated sense of self-importance—with beliefs of being unique, superior, and deserving of special treatment
  • dreams of limitless power, brightness, beauty, or the perfect love
  • believes they are exceptional and should only be associated with other special, high-status people
  • has an excessive need for admiration and a constant craving for attention, validation, and praise
  • has a sense of entitlement (i.e., expecting favorable treatment from others and feeling entitled to special privileges)
  • partakes in interpersonal exploitation, which entails taking advantage of others for personal gain, often without empathy or concern for others’ feelings or needs
  • lacks empathy and the ability to recognize or identify with the feelings and needs of others
  • feels envious of others or believes others are envious of them
  • demonstrates arrogant or haughty behaviors or attitudes

Cluster C

Cluster C personality disorders share a common theme of anxious and fearful behaviors (Figure 18.4). They are characterized by a chronic pattern of thoughts, feelings, and behaviors that are driven by a sense of fear, insecurity, and a desire for safety (Cleveland Clinic, 2022).

Chart showing Cluster C Personality Disorder traits: Avoidant, Obsessive-Compulsive, and Dependent.
Figure 18.4 The three cluster C personality disorders demonstrate anxiety and fear. (attribution: Copyright Rice University, OpenStax, under CC BY 4.0 license)


Avoidant personality disorder (AVPD) is characterized by a pervasive pattern of social inhibition, feelings of inadequacy, and hypersensitivity to criticism or rejection. It is diagnosed in individuals beginning in early adulthood with four or more of the following characteristics (APA, 2022a):

  • avoids occupational activities that involve significant interpersonal contact because of fears of criticism, disapproval, or rejection
  • is unwilling to get involved with people unless certain of being liked
  • shows restraint within intimate relationships because of the fear of being shamed or ridiculed
  • is preoccupied with being criticized or rejected in social situations
  • is inhibited in new interpersonal situations because of feelings of inadequacy
  • views self as socially inept, personally unappealing, or inferior to others
  • is unusually reluctant to take personal risks or to engage in any new activities because they may prove embarrassing


Dependent personality disorder (DPD) is characterized by a pervasive and excessive need to be taken care of by others. To be diagnosed, individuals must demonstrate five or more of the following characteristics beginning in early adulthood (APA, 2022a):

  • needs excessive amounts of reassurance and advice from others when making everyday decisions
  • requires others to take on most of the major responsibilities for their life
  • has trouble disagreeing with people since they are afraid of losing their support or acceptance
  • has trouble doing things on their own due to a lack of self-confidence
  • has a strong need for support from others to the point of volunteering to do things that are unenjoyable in order to get it
  • feels anxious or helpless when alone because of fears of being unable to care for themselves
  • is eager to seek another relationship for approval and support when a close relationship ends
  • has consuming, unrealistic fears of being left to take care of themselves

Obsessive-Compulsive Personality Disorder

Obsessive-compulsive personality disorder (OCPD) is a psychological disorder characterized by a pervasive pattern of preoccupation with orderliness, perfectionism, and control. It is diagnosed in individuals with four or more of the following characteristics beginning in early adulthood (APA, 2022a):

  • is consumed with specifics, guidelines, timetables, orders, or lists so that the main point of the action is lost
  • demonstrates perfectionism that gets in the way of finishing tasks (i.e., is unable to finish a job because they cannot reach their own excessively stringent standards)
  • is overly devoted to work to the detriment of personal hobbies and relationships
  • has an inflexible adherence to morals, ethics, or values, often with an unwillingness to compromise or bend the rules
  • is unable to discard or get rid of items, even when they have no practical value, due to a perceived need to save them or an intense emotional attachment to them
  • is hesitant to assign duties to others or collaborate with them unless they completely adopt their style of doing things
  • is stringent about saving money; tends to hoard money for future catastrophic events
  • shows rigidity and stubbornness

Obsessive-compulsive personality disorder (OCPD) is an entirely different disorder than obsessive-compulsive disorder (OCD). OCPD includes long-term personality traits characterized by extreme perfectionism, rigidity, and adherence to rules. A person with OCPD is often proud of these personality traits. Conversely, OCD includes uncontrollable, recurring thoughts (obsessions) and/or behaviors (compulsions) that cause the individual significant emotional distress. Review 17.3 Obsessive–Compulsive and Related Disorders for more details about obsessive-compulsive disorder.


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