ICD-11 classification of personality disorders
The ICD-11 classification of personality disorders is a diagnostic framework for personality disorders, introduced in the 11th revision of the International Classification of Diseases. This system of classification of personality disorders is an implementation of a dimensional model of personality disorders, meaning that individuals are assessed along continuous trait dimensions, with personality disorders reflecting extreme or maladaptive variants of traits that are continuous with normal personality functioning, and classified according to both severity of dysfunction and prominent trait domain specifiers. The ICD-11 classification of personality disorders differs substantially from the one in the previous edition, ICD-10; all distinct PDs have been merged into one: personality disorder, which can be coded as mild, moderate, severe, or severity unspecified.
Severity is determined by the level of distress experienced and degree of impairment in day-to-day activities as a result of difficulties in aspects of self-functioning, and interpersonal relationships, as well as behavioral, cognitive, and emotional dysfunctions. There is also an additional category called personality difficulty, which can be used to describe personality traits that are problematic, but do not meet the diagnostic criteria for a PD. A personality disorder or difficulty can be specified by one or more of the following prominent personality traits or patterns: Negative affectivity, Detachment, Dissociality, Disinhibition, and Anankastia. In addition to the traits, a Borderline pattern – similar in nature to borderline personality disorder – may be specified.
Background
Described as a clinical equivalent to the Big Five model, the five-trait system addresses several problems of the old category-based system. Of the ten PDs in the ICD-10, two were used with a disproportionate high frequency: emotionally unstable personality disorder, borderline type and dissocial personality disorder. Many categories overlapped, and individuals with severe disorders often met the requirements for multiple PDs, which Reed et al. described as "artificial comorbidity". PD was therefore reconceptualized in terms of a general dimension of severity, focusing on five negative personality traits which a person can have to various degrees.| ICD-11 Severity of Personality Dysfunction | DSM-5 Criterion A: level of personality functioning |
| - | No impairment |
| Personality difficulty | Mild impairment |
| Mild personality disorder | Moderate impairment |
| Moderate personality disorder | Severe impairment |
| Severe personality disorder | Extreme impairment |
| ICD-11 trait domain qualifiers | DSM-5 Criterion B: Trait domains |
| Negative affectivity | Negative Affectivity |
| Detachment | Detachment |
| Disinhibition | Disinhibition |
| Dissociality | Antagonism |
| Anankastia | |
| Psychoticism |
There was considerable debate regarding this new dimensional model, with many believing that categorical diagnosing should not be abandoned. In particular, there was disagreement about the status of borderline personality disorder. Geoffrey Reed wrote: "Some research suggests that borderline PD is not an independently valid category, but rather a heterogeneous marker for PD severity. Other researchers view borderline PD as a valid and distinct clinical entity, and claim that 50 years of research support the validity of the category. Many – though by no means all – clinicians appear to be aligned with the latter position. In the absence of more definitive data, there seemed to be little hope of accommodating these opposing views. However, the WHO took seriously the concerns being expressed that access to services for patients with borderline PD, which has increasingly been achieved in some countries based on arguments of treatment efficacy, might be seriously undermined." Thus, the WHO believed the inclusion of a borderline pattern category to be a "pragmatic compromise".
The Alternative DSM-5 Model for Personality Disorders included near the end of the DSM-5 is similar to the PD-system of the ICD-11. It was considered for inclusion in the ICD-11, but the WHO decided against it because it was considered "too complicated for implementation in most clinical settings around the world", since an explicit aim of the WHO was to develop a simple and efficient method that could also be used in low-resource settings. Research has found that the PD system of the ICD-11 aligns well with the AMPD, meaning that AMPD-related research findings are also possible to apply to the model used in the ICD-11. While there has been a limited amount of research conducted on the utility of the ICD-11 system for PD classification, studies have found favorable results.
Personality disorder
After establishing the presence of Personality Disorder, a practitioner may determine whether the patient’s level of personality problems overall corresponds to a Mild Personality Disorder, a Moderate Personality Disorder, or a Severe Personality Disorder. Severity is determined by the degree and pervasiveness of disturbance in the person’s relationships and their sense of self; the intensity and breadth of the emotional, cognitive and behavioural manifestations of the person’s disturbance; the extent to which these patterns and problems cause distress or psychosocial impairment; and the level of risk of harm to self and others. For example, some patients’ sense of self may only be contradictory or inconsistent, while other patients have a highly unstable or internally contradictory sense of self.Likewise, the patient’s situational and interpersonal appraisals may in certain cases involve some distortions but with intact reality testing, while other patients experience extreme distortions under stress, often including dissociative states or psychotic-like perceptions and interpretations. The ICD-11 classification of PD severity also incorporates harm to self and others, where patients with milder PD cause no significant harm while patients with severe PD often cause severe harm.
The ICD-11 provides a list of essential features for each of the three categories of severity, which are accompanied by a list of examples that may guide practitioners in their decision-making. These features and examples are not supposed to be used as diagnostic “criteria”; they should only be used as guidelines for a more global evaluation.
Personality disorder can also be coded as severity unspecified.
Mild personality disorder
In mild personality disorder, only some areas of personality functioning are affected. For example, a person might have difficulty making decisions or deciding on the direction of their career yet have a strong sense of self-worth and identity. Problems in many interpersonal relationships or in the performance of social and occupational roles are evident but some relationships are maintained or social roles carried out. The manifestations of a person’s difficulties are generally mild and not typically associated with harm to the self or others. For example, they may struggle to recover from minor setbacks or criticisms when stressed or they may distort how they perceive situations or other people’s motives without losing total contact with reality. Whilst the personality disturbance may be mild, the person may still experience substantial distress and impairment. The distress and impairment are limited to a narrower range of functioning or, if the difficulties span many areas, the difficulties are less intense.Moderate personality disorder
For moderate personality disorder, disturbance affects multiple areas of personality functioning such as identity, sense of self, formation and maintenance of intimate relationships, and capacity to control and moderate behaviour. Despite these difficulties, some areas of functioning may be relatively less affected. Occasionally, moderate personality disorder is associated with harm to self or others. When this is present, typically, it will be of moderate severity.Severe personality disorder
People with severe personality disorder have major disturbances in their sense of self functioning. For example, they may have no sense of who they are, experience intense numbness, or report that their beliefs and thoughts change dramatically from one context to another. Some individuals may have a very rigid view of themselves and the world and have very regimented routines and approaches to situations. The sense of self may be grandiose or highly eccentric or characterized by disgust and self-contempt.Virtually all relationships in all contexts are adversely affected. Often, relationships are very one-sided, unstable or highly conflictual. There may even be a degree of physical violence. Family relationships are likely to be severely limited or highly conflictual. The person’s ability, and sometimes willingness, to fulfil social and occupational roles is severely impaired; for example, they may be unwilling or unable to sustain regular work as a result of lack of interest, or effort, or poor performance. Alternatively, the poor work performance may derive from interpersonal difficulties or inappropriate behaviour such as angry outbursts or insubordination. Severe personality disorder is often associated with harm to the person or other people. Severe impairment is evident in all areas of the person’s life.
Personality difficulty
In addition to the personality disorder diagnosis, there is an option to assign a sub-diagnostic code for the presence of personality difficulty. While not a disorder per se, it is available as a code to inform treatment and preventive care, and is located in the section of the ICD-11 classification for non-disease entities that constitute factors influencing health status and encounters with health services. Thus, personality difficulty can be compared to the ICD-10 non-disorder codes for “accentuation of personality traits” or “borderline intellectual functioning”.Like a personality disorder diagnosis, personality difficulty is characterized by relatively stable difficulties. Such difficulties are associated with some problems in functioning which are insufficiently severe to cause notable disruption in social, occupational, and interpersonal relationships and that may be limited to specific relationships or situations. Problems with emotions, cognitions, and behaviors are only expressed intermittently or at low intensity. In contrast to mild personality disorder, the individual with personality difficulty only has some intermittent or low intensity personality-related problems, but not to the extent that it compromises the individual’s ability to keep a job, initiate and maintain friendships, and have somewhat satisfactory intimate relationships.
This code may typically be used in cases where there is an issue with personality that must be addressed or to recognize that a patient, who has undergone successful treatment of a PD, still has some residual features of the personality disturbance, which other health professionals should pay attention to. In contrast to a personality disorder diagnosis, personality difficulty is typically less complex and only limited to specific situations or relationships. Problems typically occur with less intensity or are only expressed intermittently, such as during times of stress and pressure.