DSM
According to the DSM IV (Diagnostic and Statistical Manual of Mental Disorders 4th Edition) ‘A person who suffers from borderline personality disorder has labile interpersonal relationships characterised by instability. This pattern of interacting with others has persisted for years and is usually closely related to the person’s self image and early social interactions. The pattern is present in a variety of settings (e.g. not just at work or home) and is often accompanied by a similar lability (fluctuating back and forth, sometimes in a quick manner) in a person’s affect [mood] or feelings. Relationships and the person’s affect may often be characterised as being shallow. A person with this disorder may also exhibit impulsive behaviours and exhibit a majority of the following symptoms:
1. Frantic efforts to avoid real or imagined abandonment
2. A pattern of unstable and intense interpersonal relationships characterized by alternating between extremes of idealization and devaluation
3. Identity disturbance: markedly and persistently unstable self-image or sense of self
4. Impulsivity in at least two areas that are potentially self-damaging (e.g., spending, sex, substance abuse, reckless driving, binge eating)
5. Recurrent suicidal behaviour, gestures, or threats, or self-mutilating behaviour
6. Affective instability due to a marked reactivity of mood (e.g., intense episodic dysphoria, irritability, or anxiety usually lasting a few hours and only rarely more than a few days)
7. Chronic feelings of emptiness
8. Inappropriate, intense anger or difficulty controlling anger (e.g., frequent displays of temper, constant anger, recurrent physical fights)
9. Transient, stress-related paranoid ideation or severe dissociative symptoms
Anyone with six or more of the above traits and symptoms may be diagnosed with Borderline Personality Disorder. However, the traits must be long-standing (pervasive) and there must be no better explanation for them (for example a physical illness, another mental illness or substance misuse).