Article Text


“Personality disorder” and capacity to make treatment decisions
  1. G Szmukler1,2
  1. 1
    Institute of Psychiatry, King’s College London, London, UK
  2. 2
    South London and Maudsley NHS Foundation Trust, London, UK
  1. Correspondence to Professor G Szmukler, Institute of Psychiatry, King’s College London, London, UK; g.szmukler{at}


Whether treatment decision-making capacity can be meaningfully applied to patients with a diagnosis of “personality disorder” is examined. Patients presenting to a psychiatric emergency clinic with threats of self-harm are considered, two having been assessed and reviewed in detail. It was found that capacity can be meaningfully assessed in such patients, although the process is more complex than in patients with diagnoses of a more conventional kind. The process of assessing capacity in such patients is very time-consuming and may become, in itself, a therapeutic intervention.

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Can patients with a personality disorder, by virtue of that condition alone, lack decision-making capacity? This question has been posed in discussions considering the practicability of an impaired capacity (or decision-making) criterion in mental health legislation1 2 and recently in an interesting case report,3 in which a patient with a personality disorder was refusing treatment despite having a dangerously low haemoglobin level as a result of self-cutting. The problem arises most acutely when patients with a personality disorder present in crisis with threats of self-harm, especially suicide, or of harming others.

In their case report, Winburn and Mullen3 consider the capacity of the patient to make a decision about a blood transfusion for blood loss. The role of personality disorder was seen as impairing the patient’s ability to give informed consent, because her “refusal was a manifestation of her tendency to adopt a contrary and self-destructive stance in response to clinical advice”, which in turn was a manifestation of her disturbed relationship with clinical staff. It was judged that this interaction was such “that she was considered unable to choose to behave otherwise”. The case report did not consider the patient’s capacity to make a decision about treatment for her personality disorder, although this might be considered an integral aspect of the “disorder” underlying the presenting clinical problem.

One can speculate about how a personality disorder might impair decision-making capacity. To my knowledge this question has not been specifically addressed. On the face of it, there appears to be a number of possibilities. The type of presentation most commonly calling into question a person’s capacity is one in which he or she expresses powerful suicidal ideas. An associated state of prominent emotional distress or arousal might overwhelm the ability to understand information, or to “appreciate” the nature of the situation in which the person finds themselves, or to reason. Or the person may, in an apparently calm state, claim there is no alternative to suicide. This may be in reaction to problems that may appear to others, on the surface at least, to be quite soluble. Or the suicidal intention, or impulse, may appear to be beyond the person’s control, to arise from an inner disturbance the subject finds difficult to describe or characterise. Here one might consider there may be underlying difficulties involving “appreciation” or reasoning. Matters may be more complex still when there is a suspicion that the threats of self-harm are directed at achieving an unacknowledged end, of which, perhaps, the author of the threats, himself or herself, seems unaware. On top of that, the person may, especially in an emergency psychiatric setting, reject offers of treatment, raising the question of an involuntary admission to hospital to ensure the person’s safety. The anxieties raised under these circumstances can be considerable.

Even in the absence of any specification of the underlying psychological mechanisms, there seems enough in such presentations that is “non-understandable” to make the question of capacity pertinent. It may turn out that it is not possible, in some fundamental sense—perhaps because of the particular nature of the personality disorder—to assess capacity meaningfully (unless there is another, associated mental disorder such as depression).

While working in the emergency clinic at the Maudsley Hospital we grappled with the place of capacity in the management of persons with personality disorder. Quite commonly patients with personality disorder presented who feared harming themselves or who expressed an intention to do so. We reviewed in detail two such patients who presented consecutively to the clinic as an emergency, both young women in their 20s with a primary diagnosis of personality disorder associated with serious threats of suicide and who were reluctant to accept offers of treatment. Both had a number of previous similar presentations, and had self-harmed in the past. Intoxication with drugs or alcohol was not present at the time of assessment.

Assessing treatment decision-making capacity was clearly relevant to whether patients such as these could be treated involuntarily for physical complications following self-harm (as in the case report mentioned above,3 for example, or should a patient disclose having taken an overdose of paracetamol with its potential for liver damage). Or, less clearly, in the absence of physical injury, whether they had the capacity to decide whether to accept psychiatric treatment aimed at preventing the acts of self-harm that were being threatened. This would involve treatment for some aspects of the underlying personality disorder. It was at the time of the study questionable whether the Mental Health Act (MHA) 1983 could be employed to treat a person with a diagnosis of “personality disorder”. One way of dealing with this dilemma was a consideration of treatment decision-making capacity; we reasoned that if the patient had capacity, it would provide reassurance that involuntary treatment would be unjustified ethically and that autonomously made treatment choices should be respected. (Under the MHA 2007, personality disorder is now considered to constitute a “mental disorder”, but whether this helps with ethical decision-making is a separate issue, especially if impaired decision-making is regarded as important).

Consent was not obtained from the two patients for inclusion in a published case report. Therefore many details are not provided. However, a general description of the findings should suffice to support the main conclusions.

Assessment of capacity

We adopted the MacCAT-T4 structure for the assessment of capacity. Four elements were examined: (1) “Understanding”, the patient’s ability to understand the nature of the disorder and of the benefits and risks associated with treatment; (2) “Appreciation”, the ability of the patient to appreciate that the disorder is one that the patient has and that the treatment would be of possible benefit to the patient; (3) The “ability to reason” with the information, to generate consequences of having or not having the treatment and to think about their influence on everyday activites; and (4) The ability to “make a choice”. These elements parallel the criteria in the Mental Capacity Act (MCA) 2005.5

Both patients who were assessed in detail were highly aroused or distressed on presentation to the clinic. Their ideas of self-harm were taken seriously by staff, seriously enough for compulsory admission to hospital to be entertained, initially at least. In both cases the patients said they saw no alternative to suicide. They saw treatment as useless. The criteria for a diagnosis of a depressive illness were not met.

Results of the capacity assessments

It was soon apparent that the meaning to be attributed to the concept of personality disorder was of crucial importance when thinking about treatment decision-making capacity. Despite its designation as a “mental disorder” under the MHA 2007, the conceptual status of personality disorder as a “mental disorder” is controversial. For example, Charland6 has argued that the description of personality disorder is couched in moral terms. This is most evident in “antisocial personality disorder”, in which the criteria for diagnosis are essentially a set of socially disapproved behaviours. However, I do not wish to enter into a debate on what kind of “disorder” personality disorder represents. People with personality disorder may present to healthcare services in states of distress or posing health risks and it is generally accepted that services should provide help.7 If capacity is to be assessed in this group of patients in a medical setting, then presumably personality disorder must be construed in some way as an “illness” or mental or medical “disorder”, the nature of which needs to be discussed with the patient so that his or her understanding and appreciation of the “disorder” can be tested. How is this “disorder” or “mental health problem” to be explained to the patient?

The diagnosis of personality disorder is very different to, say, that of a fracture of the femur or diabetes, or indeed to the “standard” mental disorders such as schizophrenia or bipolar disorder. A straightforward description in terms of symptoms and signs, causes, and relatively clear-cut diagnostic criteria is not possible. Personality disorder is defined as an enduring pattern of maladaptive traits, displayed in a wide range of situations, which results in harms to the person or to others. Justification of the diagnosis requires a relatively detailed account of the patient’s life history, looking at personality traits and their interactions with events or situations in which those traits led to personal or social harms or difficulties for the patient or others. Indeed, what needs to be shared with the patient is in essence a “formulation” or narrative that makes comprehensible the predicament that has brought him or her to the healthcare service. This exploration of the past and its relationship with the present takes quite a long time. It also requires a considerable degree of labour on the part of both the patient and clinician as they try to construct a meaningful account of the patient’s life and difficulties. The process involves a dialogue, in the course of which interpretations of events may need to be revised. In the two cases reviewed in detail, it also required the involvement of a relative or friend who provided an important perspective on the development of the problem, in each case instructive for both the clinician and the patient.

In the two cases here, the clinician and patient eventually substantially agreed on the main points of the formulation of the patient’s difficulties.

Next, if the patient “understands” the account, there needs to be a discussion of treatment options so the patient can think about what the outcome might be with or without treatment. Again these do not follow the conventional pattern for the majority of illnesses. In the case of personality disorder, recommendations vary greatly, and they are substantially shaped by the nature of the problems as well as a treatment modality’s acceptability to the patient. For the patients we assessed, they included in all cases the options of admission to hospital (possibly involuntary if a case could be made for a “mental disorder” under the MHA 1983), medication, “talking” treatments of various kinds (including supportive psychotherapy, cognitive behaviour therapy, dialectic behaviour therapy, family therapy, group therapy), and social interventions (including changes to accommodation, financial advice, life-style changes, including drug and alcohol misuse, social relations, work). For an assessment of capacity, the patient requires information about these interventions, including the advantages and disadvantages of each put in a way that could be reasonably expected to make sense from their point of view. Connections need to be made between the description of what comprises the personality disorder and the rationale for treatment choices. Again communicating the information to enable decision-making is very time-consuming.

Now, decision-making having been “enabled”, the patient can be asked questions directed to assessing “appreciation” and “reasoning” (or in MCA terms, “using” and “weighing” the information) leading to a choice. Consequences for his or her life goals and choices need to be generated by the patient in weighing up the frequently multiple treatment options. This is complex and again takes a lot of time.

Both patients were judged to have capacity to make treatment decisions at the end of this assessment process. Appropriate treatment options became clearer as the discussion developed. Both decided that inpatient admission was not necessary, and this was agreed by the psychiatrist and nursing team who were satisfied that the decision was soundly based. Both patients accepted referral back to their community mental health team for urgent follow-up when further discussion of treatment options, in both cases probably involving some form of psychotherapy, would be considered. Medication was not prescribed for either, but it was agreed that if their condition should deteriorate before the follow-up, they could return to the emergency clinic at any time.


Treatment decision-making capacity could be assessed in these patients with personality disorder along the lines described above and given the assumptions stated. The assessment was clearly different to what is usual in healthcare, reflecting the unusual, if not problematical, conceptual status of personality disorder as a “mental disorder”; it is certainly considerably more complex, but it was, in the end, meaningful.

However, while the assessment in these cases progressed fairly smoothly, it is clear that significant difficulties may arise in other instances. How a threshold for treatment decision-making capacity in such patients can be set is a potential concern. For example, what level of “understanding” or “appreciation” should be expected? How substantive does an agreement between the clinician and the patient on the “formulation” of the problems need to be? Whereas in the two cases discussed above there were no real disagreements, this may not always, or even generally, be the case. There is no simple answer. It is important to bear in mind a temptation for the clinician to raise the threshold when there is disagreement and when there are significant risks. Specifying the threshold in personality disorder is significantly more difficult than in patients with, say, schizophrenia or depression. In the end there may remain an element of indeterminacy if different interpretations can each be reasonably supported by the history of events and behaviours. In such cases one might conclude that it is not possible, in principle, to assess capacity; or that the patient’s account, although not the one preferred by the clinician, is an adequate one, and sufficient to demonstrate that the patient has capacity. A study of further cases would establish how significant this issue might prove. The moralised nature of some forms of personality disorder6 entails a further problem. For example, if a person with an “antisocial personality disorder” were to accept the clinician’s formulation of the problem, this could be construed as requiring an admission to engagement in socially disapproved behaviours, and an understanding that a course of “treatment” would be aimed at correcting such conduct. This is difficult to reconcile with most people’s views of “mental illness” or “mental disorder”, and is more in keeping with rehabilitation in the criminal justice system. On the other hand, it could be argued that a failure by someone with an “antisocial personality disorder” to “appreciate” that their conduct is unacceptable to society or unlawful would raise a question about their mental “capacity”, in some sense at least.

At the time the patients were seen, the MCA 2005 had not yet been implemented. However, if one were to view these patients through the lens of the MCA, it is likely that people with a personality disorder might at times, when in states of turmoil, for example, exhibit a “disturbance in the functioning of the mind or brain”, making the MCA relevant. It is also noteworthy that the nature and content of the assessments force one to pay full regard to Sections 1(3) (“A person is not to be treated as unable to make a decision unless all practicable steps to help him to do so have been taken without success”) and 3(2) (“A person is not to be regarded as unable to understand the information relevant to a decision if he is able to understand an explanation of it given to him in a way that is appropriate to his circumstances (using simple language, visual aids or any other means)”).

Two further points with a bearing on practical issues can be highlighted:

  1. The assessment of capacity along these lines was time-consuming. It could not be completed in a single interview; in each case rest-breaks were required, and time was also spent contacting relatives or friends who could help with the formulation. Informants may also be able to help with offers of support that may influence treatment choices—for example, an offer to stay with the patient for a few days could avert the need for admission to hospital. Capacity assessments during future crisis presentations by these patients might be more quickly assessed, but they will presumably still require a detailed examination of the interaction of personality with recent circumstances, and of possible treatment interventions. A diagnostic assessment of patients like these can be lengthy, but the necessary engagement in the type of dialogue described above with its constant creation of “hypotheses”, clarifications and revisions requires substantially more time.

  2. Probably as a product of the time spent with the patient and the nature of the discussion, it became evident that the assessment had become an “intervention”—and in each case we judged it be a therapeutic intervention. The patients, who had many previous contacts with mental health services, had probably never previously experienced the kind of conversation they were now engaged in. An unusual degree of detail about the patient’s life and, perhaps more notably, about the clinician’s thinking was shared. The patients seemed to find this dialogue helpful. An important outcome in these cases was that the capacity assessment ceased to be the sole, or even the main focus of the interview. What would constitute the best intervention in the light of the patient’s difficulties came to dominate the discussion.

Although both patients were eventually judged to have capacity, we do not know what proportion of all persons presenting in this way do or do not have capacity in the sense described here. One study suggests only a small proportion lack capacity.8 The findings raise a significant health service question. How far is it possible to provide a healthcare setting (short of an inpatient admission, which we generally wish to avoid) that offers the space and time for the prolonged assessment process to take place, together with the containment sufficient to ensure the person’s safety in the meantime? Most emergency departments are probably unsuitable. The psychiatric emergency clinic in which our patients were seen and which provided the right kind of environment is now closed. Providing an assessment of people with a personality disorder along the lines described above presents a considerable challenge. When the environment precludes such an assessment, an involuntary admission to hospital becomes more likely; or, if the patient is allowed to leave the emergency room, the staff may be left very anxious about the wisdom of their decision.


The author would like to thank Laurence Reed for his assistance in the emergency clinic and Matthew Hotopf, Gareth Owen and Genevra Richardson for their helpful comments on the manuscript. The author also thanks the referees for their thoughtful and stimulating comments on the initial version of the manuscript.


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  • Competing interests None.

  • Provenance and Peer review Not commissioned; externally peer reviewed.

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