Rethinking personality disorder

Abstract

People with personality disorder have difficulty interpreting the world, themselves, and the people around them. This condition manifests as problems with cognition, emotions, and behaviour, which often affect the ability to form interpersonal relationships. It is probably the most common psychiatric disorder, and almost certainly the most underdiagnosed. Popular opinion holds that the disorder is permanent, unchanging, and largely untreatable, leading the term to become more common as a pejorative label for so-called difficult patients than as an actual diagnosis. The Lancet Series on Personality disorder challenges this opinion. The problem lies in the classification of the disorder. Current definitions are largely categorical (eg, borderline personality disorder); however, in view of the high prevalence of people diagnosed with non-specific personality disorder or with as many as ten comorbid personality disorders, this model simply does not seem appropriate. Instead, the Series authors argue for a system that accounts for variation within the disorder. They propose a core diagnosis based on severity (ie, the extent to which the disorder affects the life of the individual) and a secondary set of traits describing the patient's behaviour, thus providing guidance for treatment selection. Despite the disorder often first manifesting in childhood or adolescence, the existing criteria do not allow diagnosis before the age of 18 years. This prevents health professionals from identifying and helping children and adolescents with the disorder at the time when such interventions could have the greatest effect. Furthermore, the Series describes how good outcomes can be achieved with straightforward good clinical practice by any medical practitioner with some psychiatric training. Ultimately, doctors need to lead the way in destigmatising the disorder. They are among the most likely group to come into contact with people with personality disorder and, to give the best standard of care possible, they should be able to identify it without passing judgment, and make use of the lessons learned from existing research to deliver the most appropriate treatment. Classification, assessment, prevalence, and effect of personality disorderPersonality disorders are common and ubiquitous in all medical settings, so every medical practitioner will encounter them frequently. People with personality disorder have problems in interpersonal relationships but often attribute them wrongly to others. No clear threshold exists between types and degrees of personality dysfunction and its pathology is best classified by a single dimension, ranging from normal personality at one extreme through to severe personality disorder at the other. The description of personality disorders has been complicated over the years by undue adherence to overlapping and unvalidated categories that represent specific characteristics rather than the core components of personality disorder. Full-Text PDF Personality disorder across the life courseThe pervasive effect of personality disorder is often overlooked in clinical practice, both as an important moderator of mental state and physical disorders, and as a disorder that should be recognised and managed in its own right. Contemporary research has shown that maladaptive personality (when personality traits are extreme and associated with clinical distress or psychosocial impairment) is common, can be recognised early in life, evolves continuously across the lifespan, and is more plastic than previously believed. Full-Text PDF Treatment of personality disorderThe evidence base for the effective treatment of personality disorders is insufficient. Most of the existing evidence on personality disorder is for the treatment of borderline personality disorder, but even this is limited by the small sample sizes and short follow-up in clinical trials, the wide range of core outcome measures used by studies, and poor control of coexisting psychopathology. Psychological or psychosocial intervention is recommended as the primary treatment for borderline personality disorder and pharmacotherapy is only advised as an adjunctive treatment. Full-Text PDF