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Paranoid Personality Disorder (PPD)


Mark Zimmerman

, MD, Rhode Island Hospital

Last full review/revision May 2021| Content last modified May 2021
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Paranoid personality disorders is characterized by a pervasive pattern of unwarranted distrust and suspicion of others that involves interpreting their motives as malicious. Diagnosis is by clinical criteria. Treatment is with cognitive-behavioral therapy.

Patients with paranoid personality disorder distrust others and assume that others intend to harm or deceive them, even when they have no or insufficient justification for these feelings.

From 2.3 to 4.4% of the general US population are estimated to have paranoid personality disorder. It is thought to be more common among men.

There is some evidence of increased prevalence in families. Some evidence suggests a link between this disorder and emotional and/or physical abuse and victimization during childhood.

Comorbidities are common. Paranoid personality disorder is rarely the sole diagnosis. Common comorbidities include thought disorders (eg, schizophrenia Schizophrenia Schizophrenia is characterized by psychosis (loss of contact with reality), hallucinations (false perceptions), delusions (false beliefs), disorganized speech and behavior, flattened affect... read more ), anxiety disorders 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 (eg, social phobia [social anxiety disorder]), posttraumatic stress disorder Posttraumatic Stress Disorder (PTSD) Posttraumatic stress disorder (PTSD) is recurring, intrusive recollections of an overwhelming traumatic event; recollections last > 1 month and begin within 6 months of the event. The pathophysiology... read more , alcohol use disorders Alcohol Toxicity and Withdrawal Alcohol (ethanol) is a central nervous system depressant. Large amounts consumed rapidly can cause respiratory depression, coma, and death. Large amounts chronically consumed damage the liver... read more , and another personality disorder (eg, 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 ).

Symptoms and Signs of PPD

Patients with paranoid personality disorder suspect that others are planning to exploit, deceive, or harm them. They feel that they may be attacked at any time and without reason. Even though there is little or no evidence, they persist in maintaining their suspicions and thoughts.

Often, these patients think that others have greatly and irreversibly injured them. They are hypervigilant for potential insults, slights, threats, and disloyalty and look for hidden meanings in remarks and actions. They closely scrutinize others for evidence to support their suspicions. For example, they may misinterpret an offer of help as implication that they are unable to do the task on their own. If they think that they have been insulted or injured in any way, they do not forgive the person who injured them. They tend to counterattack or to become angry in response to these perceived injuries. Because they distrust others, they feel a need to be autonomous and in control.

These patients are hesitant to confide in or develop close relationships with others because they worry that the information may be used against them. They doubt the loyalty of friends and the faithfulness of their spouse or partner. They can be extremely jealous and may constantly question the activities and motives of their spouse or partner in an effort to justify their jealousy.

Thus, patients with paranoid personality disorder can be difficult to get along with. When others respond negatively to them, they take these responses as confirmation of their original suspicions.

Diagnosis of PPD

  • Clinical criteria (Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition [DSM-5])

For a diagnosis of paranoid personality disorder, patients must have

  • A persistent distrust and suspiciousness of others

This distrust and suspicion are shown by the presence of 4 of the following:

  • Unjustified suspicion that other people are exploiting, injuring, or deceiving them

  • Preoccupation with unjustified doubts about the reliability of their friends and coworkers

  • Reluctance to confide in others lest the information be used against them

  • Misinterpretation of benign remarks or events as having hidden belittling, hostile, or threatening meaning

  • Holding of grudges for insults, injuries, or slights

  • Readiness to think that their character or reputation has been attacked and quickness to react angrily or to counterattack

  • Recurrent, unjustified suspicions that their spouse or partner is unfaithful

Also, symptoms must have begun by early adulthood.

Differential diagnosis

Clinicians can usually distinguish paranoid personality disorder from other personality disorders by the pervasiveness of its paranoia regarding others (eg, as opposed to the more transient paranoia of borderline personality) and by the core feature of each disorder:

Treatment of PPD

  • Cognitive-behavioral therapy

No treatments have been proved effective for paranoid personality disorder.

The overall high levels of suspicion and mistrust in patients make establishing rapport difficult. Expressing recognition of any validity in patients' suspicions may facilitate an alliance between patient and clinician. This alliance may then enable patients to participate in cognitive-behavioral therapy or be willing to take any drugs (eg, antidepressants, atypical antipsychotics) prescribed to treat specific symptoms. Atypical (2nd-generation) antipsychotics Second-generation antipsychotics Antipsychotic drugs are divided into conventional antipsychotics and 2nd-generation antipsychotics (SGAs) based on their specific neurotransmitter receptor affinity and activity. SGAs may offer... read more may help decrease anxiety.

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