Schizotypal Personality Disorder (STPD)

ByMark Zimmerman, MD, South County Psychiatry
Reviewed/Revised Sep 2023
View Patient Education

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 by eccentric behavior. Diagnosis is by clinical criteria. Treatment is with medications (eg, antipsychotics, antidepressants), cognitive-behavioral therapy, and sometimes supportive psychotherapy.

(See also Overview of Personality Disorders.)

In schizotypal personality disorder, cognitive experiences reflect a more florid departure from reality (eg, ideas of reference, paranoid ideas, bodily illusions, magical thinking) and a greater disorganization of thought and speech than occurs in other personality disorders.

The estimated median prevalence is 0.6% but may be as high as 3.9% (1, 2). This disorder may be slightly more common among men.

Comorbidities are common. Over half of patients with schizotypal personality disorder have had 1 episode of major depressive disorder, and 30 to 50% of them have major depressive disorder when schizotypal personality disorder is diagnosed. These patients often also have a substance use disorder.

General references

  1. 1. Pulay AJ, Stinson FS, Dawson DA, et al: Prevalence, correlates, disability, and comorbidity of DSM-IV schizotypal personality disorder: Results from the wave 2 national epidemiologic survey on alcohol and related conditions. Prim Care Companion J Clin Psychiatry 11(2):53-67, 2009. doi: 10.4088/pcc.08m00679

  2. 2. Morgan TA, Zimmerman M: Epidemiology of personality disorders. In Handbook of Personality Disorders: Theory, Research, and Treatment. 2nd ed, edited by WJ Livesley, R Larstone, New York, NY: The Guilford Press, 2018, pp. 173-196.

Etiology of Schizotypal Personality Disorder

Etiology of schizotypal personality disorder is thought to be primarily biologic because it shares many of the brain-based abnormalities characteristic of schizophrenia. It is more common among 1st-degree relatives of people with schizophrenia or another psychotic disorder.

Symptoms and Signs of Schizotypal Personality Disorder

Patients with schizotypal personality disorder do not have close friends or confidants, except for 1st-degree relatives. They are very uncomfortable relating to people. They interact with people if they have to but prefer not to because they feel like they are different and do not belong. However, they may say their lack of relationships makes them unhappy. They are very anxious in social situations, especially unfamiliar ones. Spending more time in a situation does not ease their anxiety.

These patients often incorrectly interpret ordinary occurrences as having special meaning for them (ideas of reference). They may be superstitious or think they have special paranormal powers that enable them to sense events before they happen or to read other people's minds. They may think that they have magical control over others, thinking that they cause other people to do ordinary things (eg, feeding the dog), or that performing magical rituals can prevent harm (eg, washing their hands 3 times can prevent illness).

Speech may be odd. It may be excessively abstract or concrete or contain odd phrases or use phrases or words in odd ways. Patients with schizotypal personality disorder often dress oddly or in an unkempt way (eg, wearing ill-fitting or dirty clothes) and have odd mannerisms. They may ignore ordinary social conventions (eg, not make eye contact), and because they do not understand usual social cues, they may interact with others inappropriately or stiffly.

Patients with schizotypal personality disorder are often suspicious and may think others are out to get them.

Diagnosis of Schizotypal Personality Disorder

  • Diagnostic and Statistical Manual of Mental Disorders, 5th ed, Text Revision (DSM-5-TR) criteria

For a diagnosis of schizotypal personality disorder (1), patients must have

  • A persistent pattern of intense discomfort with and decreased capacity for close relationships

  • Cognitive or perceptual distortions and eccentricities of behavior

This pattern is shown by the presence of 5 of the following:

  • Ideas of reference (notions that everyday occurrences have special meaning or significance personally intended for or directed to themselves) but not delusions of reference (which are similar but held with greater conviction)

  • Odd beliefs or magical thinking (eg, believing in clairvoyance, telepathy, or a sixth sense; being preoccupied with paranormal phenomena)

  • Unusual perceptional experiences (eg, hearing a voice whispering their name)

  • Odd thought and speech (eg, that is vague, metaphorical, excessively elaborate, or stereotyped)

  • Suspicions or paranoid thoughts

  • Incongruous or limited affect

  • Odd, eccentric, or peculiar behavior and/or appearance

  • Lack of close friends or confidants, except for 1st-degree relatives

  • Excessive social anxiety that does not lessen with familiarity and is related mainly to paranoid fears

Also, symptoms must have begun by early adulthood.

Differential diagnosis

The primary diagnostic challenge is to differentiate schizotypal personality disorder from

Differential diagnosis also includes the following:

Diagnosis reference

  1. 1. American Psychiatric Association: Diagnostic and Statistical Manual of Mental Disorders, 5th ed, Text Revision (DSM-5-TR). Washington, DC, American Psychiatric Association, 2022, pp 744-748.

Treatment of Schizotypal Personality Disorder

  • Atypical (2nd-generation) antipsychotic medications and antidepressants

  • Cognitive-behavioral therapy

  • Supportive psychotherapy

General principles for treatment of schizotypal personality disorder are the same as those for all personality disorders.

Schizotypal personality disorder is commonly treated with medications. Atypical antipsychotics lessen anxiety and psychotic-like symptoms (1); antidepressants may also help lessen social anxiety in patients with schizotypal personality disorder.

Cognitive-behavioral therapy that focuses on acquiring social skills and managing anxiety can help. Such therapy can also increase patients' awareness of how their own behavior may be perceived.

Supportive psychotherapy is also useful. The goal is to establish an emotional, encouraging, supportive relationship with the patient and thus help the patient develop healthy defense mechanisms, especially in interpersonal relationships.

Treatment reference

  1. 1. Jakobsen KD, Skyum E, Hashemi N, et al: Antipsychotic treatment of schizotypy and schizotypal personality disorder: A systematic review. J Psychopharmacol. 31(4):397-405, 2017. doi: 10.1177/0269881117695879

quizzes_lightbulb_red
Test your KnowledgeTake a Quiz!
Download the free Merck Manual App iOS ANDROID
Download the free Merck Manual App iOS ANDROID
Download the free Merck Manual App iOS ANDROID