Psychiatry· Topic 15.4 Illness behavior and personality disorders· 15.4.9

Borderline personality disorder

Borderline personality disorder is a cluster B personality disorder defined by 5 or more of 9 DSM-5 criteria spanning instability of relationships, self-image, and affect, marked impulsivity, and recurrent self-injury or suicidality; dialectical behavior therapy is the first-line treatment, with pharmacotherapy reserved as a secondary, symptom-targeted adjunct.

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What this article covers

  • Overview

    Definition: borderline personality disorder is a cluster B ("wild": dramatic, emotional, or erratic) personality disorder marked by pervasive instability of interpersonal relationships, self-image, and affect, with marked impulsivity.

  • Epidemiology

    Sex distribution: diagnosed more often in females than males.

  • Risk factors

    History of childhood trauma: patients commonly have a history of childhood trauma, including sexual abuse, which also links borderline personality disorder to dissociative identity disorder…

  • Pathophysiology

    A pervasive trait pattern: personality disorders in general are inflexible, maladaptive, rigidly pervasive patterns of behavior and perception that diverge from a person's cultural standards and…

  • Clinical features

    Diagnostic threshold: the diagnosis requires unstable interpersonal relationships and an unstable sense of self, plus at least 5 of the following 9 criteria (Diagnostic and Statistical Manual of…

  • Differential diagnosis

    Bipolar II disorder (bipolar II): the single most important mood mimic; mood lability in borderline personality disorder is persistent and pervasive, with episodes often lasting only hours to a few…

  • Diagnosis

    The diagnosis is clinical: it is established when a longitudinal pattern of unstable interpersonal relationships and an unstable sense of self is present, together with at least 5 of the 9 criteria…

  • Management

    First, start dialectical behavior therapy (DBT), the treatment of choice: DBT is a form of cognitive behavioral therapy (CBT) that adds mindfulness and emotion regulation skills, developed…

  • Complications

    Recurrent self-injury and suicide attempts: diagnostic criteria in their own right and the leading acute risk; a personality disorder diagnosis is itself a recognized risk factor for suicide.

  • Prognosis

    Treatable: despite common perceptions to the contrary, borderline personality disorder is treatable and tends to improve with appropriate care, particularly when clinicians hold clear boundaries and clarify the patient's experience.

  • Prevention

    Screen for suicidal ideation at every visit: a positive response should trigger specific questions about means and intent and a documented plan for evaluation and care.

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