It is refreshing to read a generally positive and optimistic editorial about borderline personality disorder and its long-term prognosis (Reference Fonagy and BatemanFonagy & Bateman, 2006). It is also reassuring to find the authors speculating about an issue long recognised by users of personality disorder services, that is, the ‘reality of iatrogenic harm’.

We feel, however, that there is a worrying element to this piece: the almost casual assertion that ‘in any case, in the vast majority of cases, borderline personality disorder naturally resolves within 6 years’. We question the validity of this rather astounding statement. One of the studies quoted by the authors as evidence of this (Reference Zanarini, Frankenburg and HennenZanarini et al, 2003) was a naturalistic study that assessed people at four time points (baseline and 2, 4 and 6 years) and did not document what therapy or treatment people received between assessments. It did not suggest, or even try to suggest, that borderline personality disorder ‘naturally resolves’ within 6 years.

Fonagy & Bateman also seem to imply that borderline personality disorder exists as an easily definable, distinct personality disorder, which the authors will know is very rarely, if ever, the case. People with borderline personality disorder often have other personality disorders and Axis I illnesses, as well as related alcohol and drug misuse. The idea that such complex needs will somehow spontaneously remit in 6 years is untenable.

What is particularly disturbing about this assertion is its potential political impact and the impact it may have on policy makers, coming as it does from two of the leading authorities on borderline personality disorder within the UK; indeed, from two experts who are closely involved with the development and assessment of new services for personality disorder that are currently being piloted by the Department of Health. Such a statement could be seized by a Whitehall policy advisor and taken as a perfectly adequate reason why services for people with borderline personality disorder do not need to be provided by the National Health Service, as for the vast majority of these people the problems will ‘naturally resolve’ within 6 years.

It is extremely disappointing that two such highly regarded experts in this field should perpetuate such a flagrant and dangerous simplification through the pages of this eminent Journal.