Interaction of personality disorders with other co‐occurring psychiatric disorders
Authors: JOHN M. OLDHAM
Journal: World Psychiatry (2011)

T. Widiger presents a thoughtful and balanced overview of the bidirectional ways that personality and psychopathology can influence each other. He focuses first on the differential effects that various personality types might have on the development of specific psychiatric disorders, suggesting some phenotypic similarities between personality traits (referring to the five-factor model, FFM) and features of specific disorders, such as selected eating disorders. In the clinical context of the growing interest in prevention and early intervention, it is valuable to consider whether or not certain personality types might be thought of as predictive patterns, to bring early attention to those with heritable risk for specific illnesses that might emerge during adverse environmental circumstances. Widiger does not differentiate here between personality types characterized by the FFM and personality disorders as defined by DSM-IV-TR, but similar arguments have been made about the influence of Axis II disorders on the course of Axis I disorders. In particular, a recent paper by Skodol et al 1 reported that, in a large nationally representative sample of adults with major depressive disorder (MDD), borderline personality disorder (BPD) strongly predicted persistence of MDD over time and was more strongly predictive of persistent depression than the co-occurring presence of Axis I disorders. Widiger then reviews the influence of psychopathology on personality. He contends that personality assessment will be inaccurate if carried out when a patient is experiencing an acute symptomatic episode of illness. There is some controversy about this assertion, however. Morey et al 2, for example, recently reported that personality disorders can be validly diagnosed during depressive episodes. Regarding the interactive dynamics over time, Widiger cites a report from the Collaborative Longitudinal Personality Disorders Study (CLPS), published in 2003, in which Gunderson et al 3 suggest that remission of BPD may often follow resolution of an Axis I disorder. However, the CLPS group subsequently reported that, over 3 years, the rate of remission of BPD was not affected by whether or not patients had co-morbid MDD, whereas time to remission of MDD was significantly prolonged in patients with co-occurring BPD 4. Similar findings were described in a 10-year follow-up study from the same research group 5. Widiger's summary of studies indicating that personality disorders can be understood as extreme variants of the FFM is a helpful conceptual model, one that is familiar in the medical world and similar to medical conditions such as hypertension. However, the argument that many DSM-defined personality disorders exist on a spectrum linking them to major Axis I categories is more controversial. Here, the evidence is most persuasive that patients with schizotypal personality disorder share some biomarkers and some degree of genetic risk with those at risk to develop schizophrenia. The evidence is more controversial regarding the link of other personality disorders to Axis I categories. The recognition that psychopathology, particularly if severe and persistent, can alter or shape personality is certainly persuasive in many clinical situations. How, or whether even to try, to diagnose the presence of a personality disorder in certain patients, such as patients with early onset severe and persistent schizophrenia, is certainly a legitimate question. However, even in these cases, there almost always is a “person” who has been there all along, prior to the development of the Axis I condition, and it will help us to sustain hope and a recovery framework to remember that. Sometimes the interconnectivity of conditions can be quite thorny. I recall one patient to whom I administered the Personality Disorder Examination, a semi-structured clinical diagnostic interview for DSM-defined personality disorders. I began with the usual introductory instructions that I was interested in what she was like most of her adult life, not just during a period of illness such as depression or substance abuse. She said “stop”, which I did, and she informed me that she was 35 years old, that this was her first hospitalization for severe alcoholism, and that the last time she remembered being sober was when she was 12. In a case like this, we could only learn “who she is” over time, and then only if she achieved and maintained sobriety. These and many other issues are nicely assembled in this welcome paper by Widiger, which points us in important directions for further study.