Published: 24/03/2005, Volume II5, No. 5947 Page 13

Dr Samuel P Dearman is a senior house officer and Dr Vinod Rao is a staff grade psychiatrist within Royal Preston Hospital's Department of Psychiatry.

Personality disorder is probably the least understood diagnosis, both within mental health and in the population in general. Historically, the diagnosis has been applied with little consistency.

PD may best be regarded as a way of being in the world that differs by a long way from social norms and causes harm or distress to the individual concerned or others. To add to the complexity, features usually associated with mental illness, such as disturbed mood and hallucinations, can also be involved.

One serious constraint on management is the idea of treatability. PD is defined as a disorder, which may allow treatment under the Mental Health Act. But since it is sometimes considered to be untreatable, the act may not always be used. This can mean patients with PD will receive only brief episodes of treatment that address the acute behavioural disturbances, but not the longerterm issues. This leads to dissatisfaction and resentment in both service users and professionals.

Management of PD is compounded by the frequency of unpredictable behaviour and the risk of self-harm and harm to others.

The extra demands on staff and the disruption that indirectly and directly affects other patients can lead to the stigmatisation, within health services, of those with PD.

Only 17 per cent of trusts provide a dedicated PD service, with 40 per cent providing a limited service and 28 per cent providing none.

The annual cost of managing patients with PD in the primary care setting is£3,094, compared with£1,633 for those without PD. It has also been shown that focused PD treatment programs are less costly than general psychiatric treatment.

Without a large body of evidence, the government has detailed its vision for dedicated PD services involving separate units, highly trained staff (at both the undergraduate and postgraduate level), improved case recognition, assessment under the proposed new Mental Health Act and the provision of short-term treatment and longterm rehabilitation. The government has promised funds for 2003-06, with the onus of responsibility on individual trusts to establish their own dedicated services.

A number of pitfalls might be encountered as the government proposals get under way. First, a new service may not have the capacity to cope with the deluge of referrals that may be expected. This may lead to excessive waiting lists, unrealistic demands on resources, and subsequent diminished quality of care. Second, there may be an unanticipated delay in the recruitment and training of the specialist staff required. To the authors' knowledge, extensive training programmes are not yet under way.