Borderline personality disorder and ICD-11: A chance for change

In Australia, patients with borderline personality disorder (BPD) make extensive use of both general and mental health services, posing a huge financial cost nationwide. BPD is over-represented in healthcare settings, constituting approximately one quarter of psychiatric outpatients and 1 in 10 emergency room visits (National Health Medical Research Council, 2012). As a result, most health professionals regularly encounter patients with BPD. However, the majority of health professionals acknowledge that they are poorly equipped to deal with the presentations of complex personality disorders and feel that they lack adequate training in this regard (Grenyer et al., 2017). The result is that BPD patients are often misdiagnosed, if identified at all, and are misunderstood, all of which compromise their management.

Barriers to diagnosis of BPD are varied. First and foremost, BPD is highly comorbid with other psychiatric conditions and patients often present primarily with symptoms of another illness, such as mood, anxiety or substance use disorders. In addition, they commonly fail to report the characteristic symptoms of BPD and so, without a thorough evaluation of BPD symptoms (possibly through utilisation of screening tools or semi-structured interviews), the underlying personality dysfunction is often simply missed. Second, there remains a tremendous stigma associated with the diagnosis of BPD and this results in avoidance of both assigning the diagnosis and reporting it. In part, this occurs because BPD results in interpersonal difficulties, and patients easily become alienated, especially if they display hostility and non-compliance with treatment. Stigma also stems from the misconception that BPD is ‘untreatable’, and that making a diagnosis will not inform patient management. Sometimes, the diagnosis is perceived so pessimistically that simply assigning the diagnosis is thought to confer harm. These factors are all real. However, the truth is that effective treatments have been developed and, if appropriately administered, most individuals with BPD will recover.

A third diagnostic limitation is our taxonomy. Diagnostic and Statistical Manual of Mental Disorders (5th ed.; DSM-5) and International Classification of Diseases, 10th Revision (ICD-10) are both categorical and use labels such as ‘narcissistic’, ‘avoidant’ and ‘schizoid’ personality disorder. Each has a specific set of criteria that must be met for a diagnosis to be made. The primary problem with this approach is that the various categories were not derived from research, and there remains scant evidence to support their validity. By contrast, both academics and clinicians consider personality disorder to be a dimensional construct that varies along trait domains. For personality more generally (i.e. in healthy populations), this is reflected in the popular ‘Big Five’ factor model, but, remarkably, there is no clinical equivalent. Hence, the diagnostic systems in use are out of step with the evidence base. It is perhaps not surprising then that, in general, clinicians find the current diagnostic approach to be unwieldy and inaccurate, producing diagnoses that are confusing and unhelpful.

A chance to change diagnosis

The need for a more meaningful system was recognised by both the DSM-5 Work Group for Personality and Personality Disorders and the International Classification of Diseases, 11th Revision (ICD-11) Personality Disorders Working Group. For the DSM-5 group, their approach to diagnosing personality disorders was seen as too complicated and too radical to introduce into practice and was relegated to the ‘Emerging Measures and Models’ section of the diagnostic manual, where it is likely to be ignored by most clinicians. Comparatively, the ICD-11 group has had more success with their proposal, and the new system has been published in the draft of ICD-11 to be endorsed in 2019.

The ICD-11 classification of personality disorders is dimensional, in line with thinking in the field. In this new system, personality disorder is characterised by the severity of self and/or interpersonal dysfunction, ranging from sub-threshold personality difficulty through to mild, moderate or severe personality disorder. The categories of DSM-5 and ICD-10 have been supplanted. Instead, the ICD-11 group selected five traits which are used to specify the nature of the personality disorder – negative affectivity, detachment, dissociality, disinhibition and anankastia (or obsessionality).

However, the ICD-11 Personality Disorders Working Group have not been completely successful in implementing their vision. In their original proposal (Tyrer et al., 2011), they intended for the borderline label to become obsolete – instead it would be referred to as a personality disorder with prominent negative affectivity, disinhibition and dissociality traits. This was met with two significant concerns. First, BPD is the most widely researched personality disorder, with a body of evidence spanning decades. Researchers were apprehensive that losing the label may pose a threat to research continuity and hinder ongoing advancement in the field. Second, treatments with proven efficacy have been developed specifically for BPD. Clinicians were thus concerned that a useful treatment responsiveness indicator would be lost and, furthermore, that removing the label could complicate access to treatment services.

In response to these concerns, the borderline label has been retained (Reed, 2018), and it may be used to specify the pattern of the personality disorder (e.g. moderate personality disorder, borderline type). It is not clear whether this exception will provide additional information not captured by utilising the trait domain qualifiers. Interestingly, when surveyed, most psychiatrists report that they dislike the term borderline and think that the word itself lacks meaning and is stigmatising. If field trials show that the borderline label is redundant with the trait domain qualifiers, perhaps we will see a shift in the language used to describe this pattern of illness. For the time being, however, it appears that the term borderline is here to stay.

Although the original proposal has thus been moderated, the introduction of an easy-to-use, dimensional system based on severity presents an improvement that will hopefully lead to more accurate diagnosis of BPD in practice.

A chance to change treatment

Another benefit of the ICD-11 framework is that its integration into existing clinical practice provides an opportunity to reconceptualise current approaches to treatment. Here, the implementation of stepped care mental health, where treatment intensity is determined by illness severity, is occurring in Australia at an opportune time, thanks to the Primary Health Networks program. This program is creating services that are well prepared to work alongside the ICD-11 system of personality disorder diagnoses, such that a diagnosis of severe personality disorder indicates a need for specialised treatment, while low-intensity interventions can be applied to mild and moderate personality disorders. This approach is especially important for BPD, as the vast number of people with the disorder means that highly specialised mental health services simply cannot be provided for every patient.

Indeed, while barriers to diagnosis have been discussed, another key difficulty that hinders the management of BPD patients is the perception that treatment of BPD involves extensive training and is highly demanding and time intensive for the treating clinician. However, the emergence of generalist models has shown that low-intensity interventions may be equally effective and feasible for BPD patients. A growing body of evidence has demonstrated that a single day of training for mental health professionals in a low-intensity treatment model is effective in reducing the illness severity and financial costs of BPD (Gunderson, 2018). Remarkably, this ‘good enough’ approach has ‘proven as effective as the major evidence-based psychotherapies for BPD’ (Gunderson, 2018). Importantly, the advantage of this approach is already being demonstrated by services like Project Air in New South Wales, which has been successful at providing effective care to an increasing number of personality disorder patients by utilising low-intensity, community-based interventions. Furthermore, estimates show that treating BPD leads to a saving of thousands of dollars per patient per year (Grenyer et al., 2017), as the cost of high service utilisation typical of BPD patients is reduced. It thus appears that wider adoption of low-intensity services could lead to better patient outcomes at a reduced cost to the health system.