Axis II comorbidity of borderline personality disorder.

The purpose of this study was to assess the prevalence of a full range of DSM-III-R axis II disorders in a sample of criteria-defined borderline patients and axis II controls. The axis II comorbidity of 504 personality-disordered inpatients was assessed blind to clinical diagnosis using a semistructured research interview. Odd, anxious, and dramatic cluster disorders were each common among borderline patients. However, only odd and anxious cluster disorders were significantly more common among borderline patients (N = 379) than axis II controls (N = 125). Paranoid, avoidant, and dependent personality disorders were the most highly discriminating disorders between borderline patients and controls. In addition, male and female borderline patients exhibited somewhat different patterns of comorbidity. Although the rates of avoidant and dependent personality disorders were similar, male borderlines were significantly more likely than female borderlines to meet DSM-III-R criteria for paranoid, passive-aggressive, narcissistic, sadistic, and antisocial personality disorders. These results suggest that there is a particularly strong relationship between anxious cluster disorders and borderline personality disorder (BPD). They also suggest that gender plays an important role in the expression of axis II comorbidity, particularly with respect to dramatic cluster disorders.