An editorial in the January 2006 issue of the British Journal of Psychiatry concludes that mental health professionals should be optimistic about improvements in the treatment of borderline personality disorder (BPD).
People with BPD tend to have unstable and intense relationships, and to exploit and manipulate others. They may find it difficult or impossible to recognise the effects their behaviour has on other people, to 'put themselves in other people's shoes' and to empathise with others (known as reduced 'mentalisation';).
They may have rapidly changing moods, and make recurrent attempts to self-harm, or to commit suicide. Subjectively, they have a pervasive inner feeling of emptiness and boredom.
In the past, psychiatrists tended to believe that personality disorders were intractable, and could not be effectively treated. Recently, howevre, there have been advances in understanding of the condition, and the development of psychosocial interventions, such as psychodynamic psychotherapy and dialectical behaviour therapy, which have been shown to be effective in BPD.
A review of recent research shows that the majority of patients with BPD experience a substantial reduction in their symptoms far earlier than previously assumed. After six years, 75% of patients with BPD severe enough to require hospitalisation, recover. Recurrences are rare, perhaps only 10% over six years, far fewer than with other more common mental disorders, such as depression.
Could the apparent improvement in the course of BPD be accounted for by harmful treatments being less frequently offered? The authors of the editorial comment that there may be particular disorders, including BPD, where psychotherapy represents a significant risk to the patient.
Traditional psychotherapeutic approaches depend for their effectiveness on the capacity of the individual to integrate their experience of their own mental state with the alternative perspective presented by the therapist. Mentalisation (the capacity to understand behaviour in terms of the associated mental states in self and others) is essential for the achievement of this integration.
However, people with reduced capacity for mentalisation, such as those with BPD, are unlikely to benefit from traditional psychological therapies. The difference between the patient's inner experience and the perspective given by the therapist, in the context of feelings of attachment to the therapist, leads to bewilderment and instability in the patient.
Unsurprisingly, this leads to more, rather than less, mental and behavioural disturbance. The problem is compounded by the fact that attachment and mentalisation are loosely linked psychological systems. Recent intriguing neuroscientific findings have highlighted how activation of the attachment system tends temporarily to inhibit the normal adult's capacity to mentalise.
It has been proposed that people with BPD have hyperactive attachment systems as a result of their history and/or biological predisposition, which may account for their reduced capacity to mentalise. They would be particularly vulnerable to side-effects of psychotherapeutic treatments that activate the attachment system.
Yet without activation of the attachment system, these patients will never develop a capacity to function psychologically in the context of interpersonal relationships, which is at the core of their problems.
More effective treatment lies in balancing these two components of therapy without inducing side-effects, such as arousal and disturbance in the patient. This will require more specific treatment protocols, and better focused training, if psychotherapy for borderline personality disorder is to be provided free from harm.