How common is a diagnosis of borderline personality disorder (BPD)?
The incidence and prevalence of BPD (also known as emotionally unstable personality disorder, borderline type) is affected to some extent by the diagnostic criteria used. DSM IV, favoured by the American Psychiatric Association, is more specific than the impressionistic description in ICD 10, the system favoured in the UK. However, the prevalence is generally thought to be 2% of the population, 10% of psychiatric outpatients and 30-60% of cases in a specialised personality disorder clinic. These are American figures and the numbers in the UK are probably lower because of our reluctance to make a formal diagnosis of personality disorder. (In the US, a diagnosis is needed for insurance purposes.) Nevertheless, it is an important problem for psychiatrists, community mental health teams (CMHTs), GPs and A&E departments. 2 What characteristics do typical patients with this condition exhibit? There is no such thing as a typical patient in cases of personality disorder (PD). However, typical