Narcissistic personality disorder (NPD) is a form of pathological narcissism that first appeared as a disorder in the Diagnostic and Statistical Manual of Mental Disorders in 1980, in the edition known as DSM III-TR.

As distinct from healthy narcissism, which all people possess to some extent, pathological narcissism is a maladaptive, rigid, and persistent condition that can cause significant distress and functional impairment..

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