Objective: A high rate of comorbidity among the personality disorders has been consistently identified as a problem. To address the problem of excessive comorbidity, the DSM-5 Personality and Personality Disorders Work Group recommended reducing the number of specific personality disorder diagnoses from 10 to 5 by eliminating paranoid, schizoid, histrionic, narcissistic, and dependent personality disorders. No study has examined the impact of this change. The present report from the Rhode Island Methods to Improve Diagnostic Assessment and Services (MIDAS) project examined the impact of eliminating these 5 personality disorders on the prevalence of personality disorders in a large sample of psychiatric outpatients presenting for treatment, comorbidity among the personality disorders, and association with psychosocial morbidity.
Method: From September 1997 to June 2008, 2,150 psychiatric patients presenting to the Rhode Island Hospital outpatient practice were evaluated with semistructured diagnostic interviews for DSM-IV Axis I and Axis II disorders and measures of psychosocial morbidity.
Results: More than one-quarter of the patients were diagnosed with one of the 10 DSM-IV personality disorders (28.6%, n = 614). When 5 personality disorders were excluded from consideration, then 25.8% (n = 555) were diagnosed with at least 1 of the 5 personality disorders proposed for retention in DSM-5, and the comorbidity rate dropped from 29.8% to 21.3%. Compared to patients without a personality disorder, the patients with either a retained or an excluded personality disorder had greater psychosocial morbidity. There was little difference in psychosocial morbidity between patients with a retained and an excluded personality disorder.
Conclusions: The Personality and Personality Disorders Work Group’s desired goal of reducing comorbidity would be achieved by deleting 5 personality disorders, although comorbidity would not be eliminated. The reduction of comorbidity could come with a cost of false-negative diagnoses. The results therefore do not provide unambiguous support for the DSM-5 proposed elimination of 5 personality disorders.
J Clin Psychiatry
© Copyright 2012 Physicians Postgraduate Press, Inc.
Submitted: May 10, 2011; accepted July 7, 2011.
Online ahead of print: January 24, 2012 (doi:10.4088/JCP.11m07140).
Corresponding author: Mark Zimmerman, MD, Bayside Medical Center, 235 Plain St, Providence, RI 02905 (firstname.lastname@example.org).